#include <stdio.h>int sum(int m, int n)
{int i;int sum = 0;for ( i = m; i <=n; i++){sum += i;}return sum;}int main()
{    int m, n;printf("输入m和n：\n");scanf("%d,%d", &m, &n);printf("sum = %d\n", sum(m, n));    return 0;
}