垃圾值长数据类型

Question

我需要计算一个长度约为9-10位的大数字.
Msdn 称long long类型的范围为:-9,223,372,036,854,775,808至9,223,372,036,854,775,807

但是,当我运行此代码时,我得到一个垃圾值打印:

#include <stdio.h>
int main(){
    int seed = 88888; //This will be always a 5 digit number so the square of
                      // it will be 9 or 10 digits length
    long long square = seed * seed;
    printf("square = %lld", square);
    getchar();
    return 0;
}

输出:square = -688858048

Answer 1

seed是类型的int. seed*seed也将是类型int.而88888*88888溢出的大小int.然后,您将此垃圾值分配给您的long long.

更改计算的类型seed或投射:

long long square = ((long long) seed) * seed;