#include <stdio.h> int main() { int start, end, i, j, isPrime; printf("Enter start of range: "); scanf("%d", &start); printf("Enter end of range: "); scanf("%d", &end); printf("Prime numbers between %d and %d are:n", start, end); for (i = start; i <= end; i++) { if (i < 2) continue; isPrime = 1; for (j = 2; j * j <= i; j++) { // check up to sqrt(i) if (i % j == 0) { isPrime = 0; break; } } if (isPrime) printf("%d ", i); } return 0; }