素数#include <math.h>#include <stdio.h>int main(void){ int number, flag=1, i; printf("Input n:\n"); /*************** Begin ***************/ scanf("%d", &i); /*************** End ***************/ if (flag != 0) { printf("%d is a prime number\n",number); } else { printf("%d is not a prime number\n",number); } return 0;}# include <stdio.h> int main(void){ int i, j; printf("Input n:\n"); scanf("%d", &i); for (j = 2; j <= i; j++) //保证除数是在2~被除数中间的一个数 { if (i % j == 0) //被除数刚好能被整除 break; } if (i == j) //确定能将被除数整数的是否是被除数本身，若是本身则是素数，若不是则是合数 printf("%d is a prime number\n", i); else printf("%d is not a prime number\n", i); return 0;}