 # Java Exercises: Print the number of prime numbers which are less than or equal to a given integer

## Java Basic: Exercise-217 with Solution

Write a Java program to print the number of prime numbers which are less than or equal to a given integer.

Input:

n (1 ≤ n ≤ 999,999).

Pictorial Presentation: Sample Solution:

Java Code:

`````` import java.util.Scanner;
public class Main {

public static void main(String[] args) {
System.out.println("Input the number(n):");
Scanner s = new Scanner(System.in);
int c = s.nextInt();
int ans = check(c);
System.out.println("Number of prime numbers which are less than or equal to n.:");
System.out.println(ans);
}
static int check(int c) {
boolean[] prime = new boolean[c+1];
int count = 0;
for(int i = 2; i <= Math.sqrt(c); i++) {
for(int j = i + i; j <= c; j += i) {
prime[j] = true;
}
}
for(int i = 2; i <= c; i++) {
if(!prime[i]) {
count++;
}
}
return count;
}
}

```
```

Sample Output:

```Input the number(n):
1235
Number of prime numbers which are less than or equal to n.:
202
```

Flowchart: Java Code Editor: