View Code of Problem 120

import java.util.Scanner;
 
 
public class Main {
	public static boolean isSushu(double num) {
		for(int i=2;i<=Math.sqrt(num);i++) {
			if(num%i==0) return false;
		}
		return true;
	}
	
	public static void main(String[] args) {
		Scanner scanner=new Scanner(System.in);
		while (scanner.hasNextLine()) {
			String x1=scanner.nextLine();
			String x2=scanner.nextLine();
			int x1Hour=Integer.parseInt(x1.split(":")[0]);
			int x1Minites=Integer.parseInt(x1.split(":")[1]);
			int x2Hour=Integer.parseInt(x2.split(":")[0]);
			int x2Minites=Integer.parseInt(x2.split(":")[1]);
			int sum=0;
			while (x1Hour<=x2Hour) {
				if(isSushu(x1Hour*2500+x1Minites)) {
					sum++;
					
				}
				x1Minites++;
				if(x1Hour>=x2Hour&&x1Minites>x2Minites) break;
				if(x1Minites==60) {
					x1Hour++;
					x1Minites=0;
				}
			}
			System.out.println(sum);
		}
	}
}