while循环和do-while循环

1、while循环

#include <iostream>

int main()
{
	int i = 1, sum = 0;
	while(i<=100)
	{
		sum += i;
		i++;
	}
	printf("1-100所有数字相加 = %d\n", sum);
	return 0;
}

#include <iostream>

int main()
{
	int n = 0;
	printf("请输入一个字符串：");
	while(getchar()!='\n')
	{
		n++;
	}
	printf("一共有%d个字符\n", n);
	return 0;
}

2、do-while循环

#include <iostream>

int main()
{
	int i = 1, sum = 0;
	do {
		sum += i;
		i++;
	} while (i <= 100);
	printf("1-100相加的值为：%d\n", sum);
}