#include #include //At first enter how many numbers you want to input //Then enter the numbers one by one.Press enter after each input. //The program will show the prime numbers. int find_largest_num(int ara[],int n) { int i, x; for(i = 0,x = 0;i < n;i++){ if(ara[i] > x){ x = ara[i]; } else if(ara[i] == x){ x = ara[i]; } else{ continue; } } return x; } int is_prime(int n) { int i; int r = sqrt(n); if(n < 2){ return 0; } if(n == 2){ return 1; } if(n % 2 == 0){ return 0; } for(i = 3;i <= r;i++){ if(n % i == 0){ return 0; } } return 1; } void prime_array(int ara[],int ara_cond[],int prime[],int ara_len,int prime_len) { int i, n; for(i = 0;i < ara_len;i++) { if(prime_len == 0){ if(ara[i] < 2){ ara_cond[i] = 0; } else if(ara[i] == 2){ ara_cond[i] = 1; } else{ if(1 == is_prime(ara[i])){ ara_cond[i] = 1; } else{ ara_cond[i] = 0; } } } for(n = 0;n < prime_len;n++){ if(ara[i] < 2){ ara_cond[i] = 0; } else if(ara[i] == 2){ ara_cond[i] = 1; } else{ if((ara[i]%prime[n]==0)&&(ara[i]!= prime[n])){ ara_cond[i] = 0; } } } } for(i = 0;i < ara_len;i++){ if(ara_cond[i] != 0){ ara_cond[i] = 1; } } } int main() { int a, b, m, i; scanf("%d", &a); int ara[a]; int ara_cond[a]; for(b = 0;b < a;b++){ scanf("%d", &ara[b]); ara_cond[b] = ara[b]; } int lrst_num = find_largest_num(ara, a); int x = sqrt(lrst_num); int prime[x]; for(i = 0;x >= 2;x--){ if(1 == is_prime(x)){ prime[i] = x; i++; } } int prime_len = i; prime_array(ara, ara_cond, prime, a, prime_len); printf("The prime numbers are: \n"); for(m = 0;m < a;m++){ if(1 == ara_cond[m]){ printf("%d\n", ara[m]); } } return 0; }

Find prime numbers