#include<stdio.h>int main{int i,n, sum=0;printf("请输入n值:");scanf("%d",n);for(i=1;i<=n; i++){i= i*(i+1);sum= sum+ i;
} printf("n!=%d",sum);
}
思路是对的,不过代码有问题,改成scanf(''%d'',&n);就可以了