C语言判断素数函数实现

#include <stdio.h>

int isprime(int n);

int main(){ int a; printf("input a number:"); scanf("%d", &a); printf("\n"); if (isprime(a) == 0) printf("%d is not prime", a); else printf("%d is prime", a); return 0; }

int isprime(int n) { if (n <= 1) { return 0; } for(int x = 2; x * x <= n; x++) { if(n % x == 0) { return 0; } } return 1; }