#include <stdio.h> |
int main() |
{ |
int sum = 0; //定义计算结果变量sum |
int i = 1; //定义循环数字变量i |
int flag = 1; //定义符号状态变量flag |
|
do |
{ |
sum+=i*flag; |
i++; |
flag*=-1; |
} while (i<=100); |
printf ( "%d\n" ,sum); |
} |