HansJack

#include <stdio.h>
int main()
{
	printf("Hello World!\n");

	return 0;
}

#include <stdio.h>
int main()
{	//声明 declaration
	int number = 123;
	//定义 definition
	printf("%d\n, number");
	//赋值 assignment
	return 0;
}	//Frank_PPT 讲师在这一节还讲到了TAB键与制表符的使用

identifier:
	nondigit
 	identifier
	digit

nondigit:
 	_ a b c d e f g h i j k l m n o p q r s t u v w x y z
 	A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

digit:
 	0 1 2 3 4 5 6 7 8 9

add
ADD
Add
aDD

j
count
temp1
top_of_page
skip12
LastNum

//行
    注释

/*
        块
	注
	释
*/

//int 变量
#include <stdio.h>

int main(){
	//integer 赋值
	int sun_flower = 9673;

	printf("阳光目前的数值：%d\n", sun_flower);

	return 0;
}

#include <stdio.h>
int main()
{
	int number = 100;
	//以十进制表示
	printf("Decimal: %d\n", number);

	printf("Octal: %o\n", number);

	printf("Hexadeciaml (lowercase) : %x\n", number);

	printf("Hexadeciaml (uppercase) : %X\n", number);

	return 0;
}

#include <stdio.h>

int main() {

	float temperture = 36.5f;

	float humidity = 48.3f;

	float speed_of_sound = 343.5e2f;

	float lenght = 12.3f, width = 23.45f, height = 34.56f;

	printf("Temperture: %f\n", temperture);
	printf("Humidity: %f\n", humidity);
	printf("Speed_of_Sound: %f\n", speed_of_sound);
	printf("Lenght: %f x %f x %f\n", lenght width height);
//丢失精度
//double %lf , float %f
	return 0;
}

#include <stdio.h>

int main () {

float num = 123.456;

printf("Using %%f: %f\n", num);

//%e %E 科学计数法格式化输出
ptintf("Using %%e: %e\n", num);
printf("Using %%E: %E\n", num);

//%a %A 十六进制浮点数 p计数法
printf("Using %%a: %a\n", num);
printf("Using %%A: %A\n", num);

return 0;
}

#include <stdio.h>
#include <float.h>//点开看看

int main() {

	float max_float = FLT_MAX;

	float overflow = max_float * 1000.0f;
	//OverFlow 上溢

	float min_float = FLT_MIN;

	float underfloat = min_float / 1000.0f;
	//UnderFlow 下溢

	printf("Maximum Float: %e\n", max_float);
	printf("OverFloat: %e\n", overflow);
	printf("Minimum Float: %e\n", min_float);
	printf("UnderFloat: %e\n", underfloat);

	return 0;
}

#include <stdio.h>
#include <float.h>
#include <math.h>

int main() {

	//正无穷大
	float positive_infinty = INIFITY;
	printf("Positive Infinity: %f\n", positive_infinty);

	//负无穷大
	float negative_infinty = -INIFITY;
	printf("Negative Infinity: %f\n", negative_infinty);

	//除以0产生的无穷大
	float num = 1.0f;
	float inifity = num / 0.0f;
	printf("0.0 / 0.0 = %f\n", nan);

	//Nano 0/0
	//float nan = 0.0f /0.0f;
	//printf("0.0f / 0.0f =%f\n", nan)

	//对负数开平方跟
	float negative_sqrt = sqrt(-1.0f);
	printf("sqrt(1.0f) = %f\n", nefative_sqrt);

	return 0;
}

#include <stdio.h>

int main() {

	//四舍五入
	//IEEE 754
	//最近偶数舍入  round to nearest, ties to even
	//银行家舍入

	//3.14159
	float number = 3.14159f;
	printf("%.4f\n", number);

	//3.15
	//3.25
	return 0;
}

#include <stdio.h>

int main() {

	//double

	//float 丢失精度

	//3D渲染

	//利息 NASA

	//浮点常量 3.14
	//3.14 默认double类型 特别注明3.14f

	return 0；

}

#include <stdio.h>

int main() {
 
	float float_num 1.0 / 3.0;
	double double_num = 1.0 / 3.0;

	printf("Float precision: %20f\n", float_num);
	printf("Double precision: %.20lf\n", double_num);
	//float 和 double 有效精度的对比
	printf("Defined max precision for double: %d\n", FLT_DIG)
	printf("Defined max precision for float: %d\n", DBL_DIG)

	//53除以log₂10  24除以log₂10  即为精确度

}

#include <stdio.h>

int main() {

	char mych = 'a'; //实际用int类型 存储， 将A转化成int类型 int(97)

	printf("mych: %c\n")；

	//ASCII美国信息标准代码 一般使用7bit 包括128个字符


}

清除屏幕 print("\033[2J");
移动光标 print("\033[%d;%dH", 3, 3);

#include <stdio.h>
#include <stdbool.h>

int main() {
	//true or false
	//转换成 1 or 0

	bool is_game_win = true;
	bool is_game_over = false;

	return 0;
}

#include <stdio.h>
#define PI 3.14

int main() {
	//常量

	const double MAX_USER = 100;

	printf("PI: %lf\n", PI);

	return 0;

}

#include <stdio.h>
#include <stdint.h>
#include <inttype.h>
int main() {

	//数据对象
	//左值 Lvalue
	//右值 Rvalue
	//运算符
	uint32_t apple_box = 5;

	uint32_t orange_box = 5;

	printf("苹果盒子里面有 %" PRIu32 "个苹果\n", apple_box);
	printf("橘子盒子里面有 %" PRIu32 "个橘子\n", orange_box);

	uint32_t total_fruit = apple_box + orange_box;

	printf("盒子里面有 %" PRIu32 "个水果\n", total_box);
 
	return 0;

}

#include <stdio.h>
#include <stdint.h>
#include <inttype.h>
int main() {

	int32_t value = 5;
	int32_t result_1;
	int32_t result_2;

	//后缀递增，先赋值，再++
	result_1 = value++;
	//前缀递减，先--，后赋值
	result_2 = --value;
	printf("After postfix increment, result_1 = %" PRIu32 ",result_2 = %" PRIu32 ", value = %" PRIu32 "\n", result_1, result_2, value);

	return 0;

}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	uint8_t num = 22;
	num >> 2;//高位补零，低位排挤

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	uint8_t num = 22;
	//num >> 2; 高位补零，低位排挤

	uint8_t num = 22;
	printf("Original number: %" PRIu8 " (binary: 00010110)\n", num);

	uint8_t left_shifted = num << 2;
	printf("Left shifted by 2: %" PRIu8 " (binary: 01011000)\n", num);

	uint8_t right_shifted = num >> 2;
	printf("Right shifted by 2: %" PRIu8 " (binary: 00000101)\n", num);

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	uint8_t num = 25;

	//uint32_t result = num * 1024;
	printf("Result: %" PRIu32 "\n", result);
	ALU 负责 基本的运算

	return 0;
}

include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	int a = 10;
	int b = 20;
	//xxx ? xxx : xxx 判断true or false
	bool greater = a > b;
	printf("a > b: %d\n", greater);
	printf("a > b: %s\n", greater ? "true" , "false");

	bool less = a < b;
	printf("a < b: %d\n", less);
	printf("a < b: %s\n", less ? "true" , "false");

	bool not_equal = a != b;
	printf("a != b: %d\n", not_equal);
	printf("a != b: %s\n", not_equal ? "true" , "false");

	bool equal = a == b;
	printf("a == b: %d\n", equal);
	printf("a == b: %s\n", equal ? "true" , "false");

	bool greater_or_equal = a >= b;
	printf("a >= b: %d\n", greater_or_equal);
	printf("a >= b: %s\n", greater_or_equal ? "true" , "false");

	bool less_or_equal = a <= b;
	printf("a <= b: %d\n", less_or_equal );
	printf("a <= b: %s\n", less_or_equal ? "true" , "false");

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	int score = 89;

	printf("你的成绩等级：%s\n", score >= 60 ? "及格" : "不及格");

	return 0;
}

#include 
int main() { 
	int score = 85; 
	// 你可以根据需要修改这个分数 
	const char* result = (score >= 90) ? "优秀" : (score >= 85) ? "一般" : (score >= 60) ? "合格" : "不及格"; printf("%s\n", result); 

	return 0; 
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	int a = 12;
	int b = 25;

	// & 二进制 位位比较 都是1才输出1 比如
	printf("%d\n", 12 & 25);
	//将特定位清零、检查某一位是否为1

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	int a = 2;
	int b = 5;

	// | 二进制 位位比较 有1就输出1 比如0111 
	printf("%d\n", a | b);
	//设置特定位、组合标志位

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	int a = 2;
	int b = 10;

	// ^ 二进制 位位比较 有1 0才输出1 比如1000 
	printf("%d\n", a ^ b);
	//逻辑异或 XOR操作
	//翻转特定位、交换两个变量值、检查不同

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

void print_binary(uint8_t num);

int main() {

	uint8_t status = 0b00001100;	//初始状态

	printf("Initial status: 0b");
	print_binary(status);
	printf("\t(Binary)\n");

	status = status & 0b11111011;	//mask掩码 异或 控制
	printf(("Fanal status: 0b");
	printf("\t(Binary)\n");
	return 0;
}

void print_binary(uint8_t num);
	for (int index = 7; index >= 0; index--) {
	    printf("%d", (num >> index) & 1);
	}
}

#include <stdio.h>
/*
struct BigStruct {
	//..
	//..
};

void uodate(BigStruct& bs) {
	BigStruct temp = someExp();

	bs = bs + temp;

	bs += temp;

}
*/


int main() {

	int base_number = 8;
	int add_number = 2;
	int sub_number = 3;
	int mul_number = 2;
	int div_number = 5;
	int mod_number = 4;

	base_number += add_number;
	//In-place Modification 原地修改

	base_number -=
	base_number *=
	base_number /=
	base_number %=
	base_number <<=
	base_number >>=
	base_number &=
	base_number |=
	base_number ^=

	return 0;

}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	uint32_t a = 1, b = 2, c = 4;

	uint32_t result = (a += 1, b -= 1, c += 3);

	printf("a = %d, b = %d, c = %d, result = %d", a, b, c, result);

	return 0;

}

// cpp_comma_operator.cpp
#include <stdio.h>
int main () {
   int i = 10, b = 20, c= 30;
   i = b, c;
   printf("%i\n", i);

   i = (b, c);
   printf("%i\n", i);
}

20
30

func_one( x, y + 2, z );
func_two( (x--, y + 2), z );

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main() {

	int32_t result;

	result = a * b + c << d >e ? b : c * sizeof(++e) / sizeof(int32_t);

	printf(Result: %" PRId32 ", result);

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttype.h>
#include <stdbool.h>

int main() {

	uint32_t number = 100;

	//if 语句
	if (number > 10) {
		printf("这个数大于10！\n");
		printf("这个数大于10！\n");

	}

	if (number >=100) {
		printf("这个数大于等于100！\n");


	} 
	else {
		printf("这个数小于100！\n");

	}


	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttype.h>
#include <stdbool.h>

int main() {

	bool is_weather_sunny = false;
	bool is_venue_available = true;

	if (is_weather_sunny && is_venue_available) {
		printf("活动如期举行!\n");
		}
	else {
		printf("活动不能如期举行!\n")；
	if (!is_weather_sunny) {
		printf("原因：天气不晴朗！\n")
		}
	if (!is_vueue_available) {
		printf("原因：没有场地!\n")
		}

	return 0;
}

//自动贩卖机
//只支持硬币
#include <stdio.h>
#include <stdbool.h>
#include <inttypes.h>

int main(void)

{

	const uint32_t PRICE = 3;	//drink's price

	uint32_t balance = 0;		//now total_coin

	uint32_t coin;				//every coin in it

	puts("drink's price is $5 please!");

	while (balance < PRICE)	//在投够数额前
	{
		puts("don't!");	//拒绝交易

		scanf_s("%" PRIu32, &coin);


		if (coin == 1 || coin == 2 || coin == 5) //确定金额类型
		{
		balance += coin;	//赋值 加等

		printf("你已经投入 $%" PRIu32 "\n", balance);
		}
		else {

		printf("sorry!我们不接受 $%" PRIu32 "的硬币\n", coin);
		}
	}

	if (balance > PRICE) {
		printf("找零：%" PRIu32 "\n", balance - PRICE);
	}
	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <inttypes.h>

int main(void)
{

		//玩家进入不同条件的房间

	uint32_t coins= 15;
	bool is_vip = true;
	bool have_special_tool = false;

	if (is_vip) {
		puts("vip Enter!\n");
	}
	else {
		puts("not_vip Exit!\n");
	}

	if (coins >= 10 || have_special_tool) {
		puts("Enter!\n")
	}
	else {
		puts("Exit!\n");
	}
	return 0;
}

#include <stdio.h>
#include <stdbool.h>
#include <inttypes.h>

int main(void)
{
	const uint32_t all_laps = 100;

	uint32_t current_laps = 0;

	puts("开始!");

	while (current_laps < all_laps)
	{
		current_laps++;

		printf("完成第 %"PRIu32"圈。\n", current_laps);
	}
	return 0;
}

//自动贩卖机
//只支持硬币
#include <stdio.h>
#include <stdbool.h>
#include <inttypes.h>

int main(void)

{

	const uint32_t price = 10;	//drink's price

	uint32_t balance = 0;		//now total_coin

	uint32_t coin;				//every coin in it

	puts("drink's price is $5 please!");

	while (balance < price)	//在投够数额前 只有在够的时候才开始循环
	{
		puts("don't!");	//拒绝交易

		//模拟投币
		scanf_s("%" priu32, &coin);


		if (coin == 1 || coin == 2 || coin == 5) //确定金额类型
		{ 
		balance += coin;	//赋值 加等 计数

		printf("你已经投入 $%" priu32 "\n", balance);
		}
		else {

		printf("sorry!我们不接受 $%" priu32 "的硬币\n", coin);
		}
	}

	if (balance > price) {
		printf("找零：%" priu32 "\n", balance - price);
	}
	return 0;
}

//一定要写printf 可以看到效果。

//遇到循环问题
//不要在循环中多次运用，来避免不必要的错误

//写一个计算机求和


#include <stdio.h>
#include <inttypes.h>

int main(void)
{
	uint32_t sum = 0;	//设置初始数字和为0

	uint32_t number = 1;	//第一次number的值

	while (number != 0)	//设置0为退出循环的方法
	{
		scanf_s("%" PRIu32, &number);	//scanf重新赋值number，第一次number值实际没有用到。
		sum += number;
	}

	printf("所求的和sum是 %" PRIu32 "\n", sum);

	return 0;
}

#include <stdio.h>
#include <inttypes.h>
#include <stdbool.h>
#include <stdlib.h>
#include <limits.h>
#include <errno.h>

int main()
{
	uint32_t sum = 0;	//设置初始数字和为0

	char input[50];	//我们将用户输入的字符转换成数字

	char* end;

	puts("请输入一系列数字，用回车隔开，我们计算他们的和,输出q结束");

	while (true)	//设置0为退出循环的方法
	{
		errno = 0;

		puts("输入一个数字：");

		scanf_s(" %49s", &input, 50);

		if (input[0] == 'q' && input[1] == '\0') {
			break;
		}

		long number = strtol(input, &end, 10);
		//将输入的字符转换成数字，并且加到总和sum中
		//0的ASCII为48
		if (end == input || *end !='\0') {
			printf("无效输入，请输入一个数字或是字符q\n");

		}
		else if (errno == ERANGE || number < 0 || number > UINT32_MAX){
			printf("数字超出范围！请输入小于或等于 %u 的正整数\n", UINT32_MAX);
		}
		else {
			sum += (uint32_t)number;
		}

	}

	printf("所求的和sum是 %" PRIu32 "\n", sum);

	return 0;
}

#include <stdio.h>
#include <inttypes.h>
#include <stdbool.h>

int main()
{
	uint32_t sum = 0;	//设置初始数字和为0

	uint32_t number;	//第一次number的值

	puts("请输入一系列数字，用回车隔开，我们计算他们的和,输出0结束");

	while (true)	//设置0为退出循环的方法
	{

		scanf_s(" % " PRIu32, &number);

		if (number == 0) {
			break;
		}

		sum += number;
	}

	printf("所求的和sum是 %" PRIu32 "\n", sum);

	return 0;
}

//卫语句的使用：租车案例
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <inttypes.h>

void check_car_rent(uint8_t age, uint8_t driving_exp_years);

int main(void) 
{
	check_car_rent(22, 3);

	return 0;
}

void check_car_rent(uint8_t age, uint8_t driving_exp_years) {
//卫语句
	if (age < 21) {
		puts("不符合条件，年龄不足！");
		return 0;
	}

	if (driving_exp_years < 1) {
		puts("不符合条件，驾驶年龄不足!");
		return 0;
	}
}

//简化逻辑表达式
#include <stdbool.h>
#include <inttypes.h>

int main(void) 
{
	//逻辑表达式应该简化！
	bool is_weekend = true;
	bool has_enter = true;

	if (!has_enter) {
		return 0;
	}

	return 0;
}

#include <stdbool.h>
#include <inttypes.h>

int main(void)
{
	//状态机：管理复杂状态的转换，使用switch case

	uint8_t traffic_state = 0;

	switch (traffic_state)
	{
	case 0:
		puts("red");
		traffic_state = 1;
		break;
	case 1:
		puts("yellow");
		traffic_state = 2;
		break;
	case 2:
		puts("green");
		traffic_state = 0;
		break;
	default:
		puts("???");
		break;
	}

	return 0;
}

//switch-case 与 if-else 的区别
#include <stdio.h>
#include <stdbool.h>
#include <inttypes.h>

int mian(void)
{


	return 0;
}

//循环在生活中的作用


#include <stdio.h>
#include <stdbool.h>
#include <inttypes.h>

int main(void)
{
	int32_t number;

	scanf_s("请输入: %d %d %d", &number, &number, &number);//在实际开发中不用scanf
	//not write \n in it
	printf("已经扫描到你输入的数字为: %d %d %d\n", number, number, number);

	return 0;
}

//do-while 和 while 的区别

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main(void)
{
	uint32_t total_laps = 10;

	uint32_t current_laps = 0;

	puts("罚跑开始！");

	do {

		current_laps++;
		printf("跑步者完成第%" PRIu32 "圈\n", current_laps);
	} while (current_laps < total_laps);

	return 0;
}

//do-while 的实际作用

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

int main(void)
{

	uint32_t choice;

	do 
	{

		puts("****主菜单****");
		puts("1. 新游戏");
		puts("2. 载入游戏");
		puts("3. 退出");
		scanf_s("%" PRIu32, &choice);

		switch (choice) 
		{
		case 1:
			puts("****创建新游戏！");
			break;
		case 2:
			puts("****载入存档！");
			break;
		case 3:
			puts("****退出游戏！");
			break;
		}

	} while (choice != 3);

	return 0;

}

//随机数猜数游戏案例
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <time.h>
#include <stdlib.h>

int main(void)
{
	uint32_t secret_num, guess, status;
	char buffer[50];

	srand(time(NULL));
	//生成1-100的随机数
	secret_num = rand() % 100 + 1;

	puts("猜猜嘛！");

	do {
		puts("请输入你猜的数：");

		fgets(buffer, sizeof(buffer), stdin);
		status = sscanf_s(buffer, "%d", &guess);
		//卫语句
		if (status != 1) {
				puts("输入无效！");
				continue;
		}

		if (guess < secret_num) {
			puts("太小了！");
		}
		else if (guess > secret_num) {
			puts("太大了！");
		}

	} while (guess != secret_num);

	printf("恭喜你，猜对了！");

	return 0;
}

//continue语句
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>

int main(void) {

	uint32_t sum = 0;
	int32_t number;

	puts("请输入一系列的正整数,可以输入负数,输入0结束");

	while (1) {
		puts("请输入一个数字");

		scanf_s("%d", &number);

		if (number == 0) {
			break;
		}
		if (number < 0) {
			continue;	//continue 直接跳过这次循环
		}
		sum += number;//计数
	}
	printf("计算结果为：%" PRIu32 "\n", sum);

	return 0;

}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
int main() {
    uint32_t number;
    
    puts("请输入数字（0-100），输入-1后结束程序");
    
    while (1) {
        puts("请输入一个数字：");
        scanf_s("%d", &number);
        //卫语句！检查条件结束
        if (number == -1) {
            break;
        }
        if (number < 0 || number > 100) {
            continue;//跳过本次循环的剩余部分。
        }
        sum += number;
    }
    
    return 0;
}

//初探for循环
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>

int main(void)
{
	//for循环
	const uint32_t total_laps = 10;	//目标圈数

	//uint32_t current_lap = 0;	初始化当前圈数

	puts("跑步者开始跑步");

	for (uint32_t current_lap = 0;current_lap <= total_laps;current_lap++) {
		printf("跑步者完成第 %" PRIu32 " 圈\n", current_lap);
	}

	return 0;

}

//整数平方求和
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>

int main(void)
{
	 /*
		目的为了计算从1到n（n由玩家输入）的所有整数的平方和

	 */
	uint32_t number;

	uint32_t sum_of_squares = 0;

	puts("输入整数n");

	scanf_s("%u", &number);

	for (uint32_t index = 1; index <= number; index++) {
		sum_of_squares += index * index;
	}

	printf("%" PRIu32 "\n", sum_of_squares);
	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>

int main(void) {

	/*
		星光大道
		倒数五个数
	*/

	uint32_t start_number;
	
	puts("Please enter a positive integer");
	scanf_s("%" SCNu32, &start_number);

	puts("The countdown begins");
	for (uint32_t index_number = start_number; index_number > 0; index_number--)
	{
		printf("%" SCNu32 "\n", index_number);
	}
	puts("The countdown stop");
	return 0;
}

//扩展sleep
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <windows.h>

int main(void) 
{

	/*
		星光大道
		倒数五个数
	*/

	uint32_t start_number;
	
	puts("Please enter a positive integer");
	scanf_s("%" SCNu32, &start_number);

	puts("The countdown begins");
	for (uint32_t index_number = start_number; index_number > 0; index_number--)
	{
		printf("%" SCNu32 "\n", index_number);
      Sleep(1000);
	}
	puts("The countdown stop");
	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <windows.h>
//阶乘

int main(void) {

	uint32_t number;
	uint32_t factorial = 1;

	puts("Please enter a positive integer :");
	scanf_s("%" SCNu32, &number);

	for (uint32_t index = 1; index <= number; index++) {
		factorial *= index;
	}

	printf("%" PRIu32 "! = %" PRIu32 "\n", number, factorial);

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <math.h>
#include <stdbool.h>

int main(void)
{
	double number = 4.00;

	printf("%lf\n", sqrt(121));

	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <math.h>
#include <stdbool.h>

int main(void)
{
	uint32_t num;

	bool is_prime = true;

	puts("Please enter a positive integer,except for 1,we will check if it is prime:");

	scanf_s("%" SCNu32, &num);

	if (num <= 1) {
		is_prime = false;
	}
	else {
		//for , 检查除了1和它本身之外的因数
		for (uint32_t i = 2; i * i <= num; i++) {
			if (num % i == 0) {
				is_prime = 0;
				break;
			}
		}
	}
	return 0;
}

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <math.h>
#include <stdbool.h>

int main(void)
{
	uint32_t size;
	puts("请输入图案的大小: ");
	scanf_s("%" SCNu32, &size);

	//特点：长和宽一样
	puts("打印正方形图案");

	for (uint32_t i = 0; i < size; i++) {
		for (uint32_t j = 0; j < size; j++)
		{
			printf("* ");
		}
		printf("\n");
	}
	return 0;
}