Problem:
Score : 100 points

Problem Statement

You will turn on the air conditioner if, and only if, the temperature of the room is 30 degrees Celsius or above.

The current temperature of the room is X degrees Celsius. Will you turn on the air conditioner?

Constraints

-40 \leq X \leq 40

X is an integer.

Input

Input is given from Standard Input in the following format:

X

Output

Print Yes if you will turn on the air conditioner; print No otherwise.

Sample Input 1

25

Sample Output 1

No

Sample Input 2

30

Sample Output 2

Yes

Solution in Java (OpenJDK 11.0.6) (judge verdict: Accepted)

import java.io.IOException;
import java.io.InputStream;
import java.util.NoSuchElementException;
import java.util.*;

class FastScanner {
    private final InputStream in = System.in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;

    private boolean hasNextByte() {
        if (ptr < buflen) {
            return true;
        } else {
            ptr = 0;
            try {
                buflen = in.read(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (buflen <= 0) {
                return false;
            }
        }
        return true;
    }

    private int readByte() {
        if (hasNextByte())
            return buffer[ptr++];
        else
            return -1;
    }

    private static boolean isPrintableChar(int c) {
        return 33 <= c && c <= 126;
    }

    public boolean hasNext() {
        while (hasNextByte() && !isPrintableChar(buffer[ptr]))
            ptr++;
        return hasNextByte();
    }

    public String next() {
        if (!hasNext())
            throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while (isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }

    public long nextLong() {
        if (!hasNext())
            throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b) {
            throw new NumberFormatException();
        }
        while (true) {
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            } else if (b == -1 || !isPrintableChar(b)) {
                return minus ? -n : n;
            } else {
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }

    public int nextInt() {
        long nl = nextLong();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE)
            throw new NumberFormatException();
        return (int) nl;
    }

    public double nextDouble() {
        return Double.parseDouble(next());
    }
}

public class Main {
    static int MOD = 1000000007;

    public static class Mas {
        int x;
        int y;
        int step;

        Mas(int x, int y, int step) {
            this.x = x;
            this.y = y;
            this.step = step;
        }
    }

    static long pow(long l, long i) {
        if (i == 0)
            return 1;
        else {
            if (i % 2 == 0) {
                long val = pow(l, i / 2);
                return val * val % 2019;
            } else {
                return pow(l, i - 1) * l % 2019;
            }
        }
    }

    private static final int[] vX = { 1, 0, 0, -1 };
    private static final int[] vY = { 0, 1, -1, 0 };

    static class Edge {
        int idx;
        int node;

        public Edge(int n, int i) {
            this.idx = i;
            this.node = n;
        }
    }

    static int stocks = 0;
    static long maxProfit(int k, int[] prices) {
        int n = prices.length-1;
        if (n <= 1)
            return 0;
        long maxPro = 1000;
        int idx = 0;
            for (int i = 0; i < n; i++) {
                if (prices[i + 1] < prices[i]) {
                    maxPro += (maxPro / prices[idx]) * (prices[i] - prices[idx]);
                    idx = i+1;
                   
                    // System.out.println("sotck"+stocks);
                } 
                // System.out.println("money　"+maxPro+"stock　"+stocks+"price"+prices[i]);
                // System.out.println(maxPro);
                    
            }
            return Math.max(maxPro,1000);
    }

    public static void main(String[] args) throws IOException {
        FastScanner fs = new FastScanner();
        int n = fs.nextInt();
      System.out.println(n>=30 ? "Yes":"No");
       
    }
}