Calculate the formula 公式计算

Question

Problem Description
You just need to calculate the sum of the formula: 1^2+3^2+5^2+……+ n ^2.

Input
In each case, there is an odd positive integer n.

Output
Print the sum. Make sure the sum will not exceed 2^31-1

Sample Input
3

Sample Output
10

Answer 1

#include<stdio.h>
#include<math.h>
int main()
{
    int i,n;
    int sum;
    printf("Please input num n:\n");
    scanf("%d",&n);
    for(i = 1;i <= n;i+=2)
    {
        sum += pow(i,2);
    }
    if(sum<pow(2,31))
        printf("sum=",sum);
    else
        printf("The sum is too big!");
    return 0;
}