编写一个程序，由键盘输入n值，求s=1+(1+2)+(1+2+3)+…+(1+2+3+…+n)的值。

Question

如题所述

Answer 1

#include <stdio.h>int main()
{
int sum = 0, n;
puts("enter n:");
scanf("%d", &n);
for (int i=1; i<=n; ++i){
for (int j=1; j<=i; ++j){
sum += j;
}
}
printf("result: %d\n", sum);
return 0;
}

Answer 2

#include <stdio.h>
int main()
{
int n,i,sum=0;
scanf("%d",&n);
for( i=1;i<=n;i++)
{sum+=sum+i;
}
printf("%d",sum);
return 0;
}本回答被网友采纳