pc006.c (1087B)
1 /* 2 * Author : Amit Dutta <amitdutta4255@gmail.com> 3 * Date : 12 Dec 2025 4 * Repo : https://github.com/notamitgamer/bsc 5 * License : MIT License (See the LICENSE file for details) 6 */ 7 8 /* Prime number check */ 9 10 #include <stdio.h> 11 #include <math.h> 12 13 int main() 14 { 15 int num, i, temp; 16 printf("Enter the number : "); 17 if(scanf("%d", &num) != 1) { 18 printf("Only postive number allowed."); 19 return 1; 20 } 21 if(num <= 0) { 22 printf("\nOnly potive number are allowed."); 23 return 1; 24 } 25 if(num == 1) { 26 printf("\nInput 1 is not a prime number."); 27 return 0; 28 } 29 if(num == 2) { 30 printf("\nInput 2 is a prime number."); 31 return 0; 32 } 33 if(num % 2 == 0) { 34 printf("\nInput %d is not a prime number.", num); 35 return 0; 36 } 37 temp = (int)sqrt(num); 38 for (i = 3; i <= temp; i += 2) 39 { 40 if (num % i == 0) 41 { 42 printf("\nInput %d is not a prime number.", num); 43 return 0; 44 } 45 } 46 printf("\nInput %d is a prime number.", num); 47 return 0; 48 }