C语言求累加

#include<stdio.h>void main(){    int n=100;    printf("%d\n",sumFor(n));    printf("%d\n",sumWhile(n));    printf("%d\n",sumRecursion(n));}int sumFor(int n){    int sum=0;    int i;    for(i=1;i<=n;i++)    {        sum+=i;    }    return sum;}int sumWhile(int n){    int sum=0;    int i=1;    while(i<=n)    {        sum+=i++;    }    return sum;}int sumRecursion(int n){    if(n<=1)//终止条件        return 1;    return n+sumRecursion(n-1);}

结果：

505050505050