Language: C

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;

using static Input;
//using static Util;
class Program
{
    static string S;
    static void INPUT()
    {
        S = NextString();
    }
    static void OUT()
    {
        var b = false;
        foreach (var c in S)
        {
            b |= c == '7';
        }

        Console.WriteLine(b ? "Yes" : "No");
    }
    static void Main(string[] args)
    {
#if DEBUG  
        //TESTINPUT();
        INPUT();

#else
        INPUT();
#endif
        OUT();
    }

    static void TESTINPUT()
    {
    }

}

public class Input
{
    public const long MOD = 1000000007;
    public const int INF = 1000000007;
    private static Queue<string> q = new Queue<string>();
    private static void Confirm() { if (q.Count == 0) foreach (var s in Console.ReadLine().Split(' ')) q.Enqueue(s); }
    public static int NextInt() { Confirm(); return int.Parse(q.Dequeue()); }
    public static long NextLong() { Confirm(); return long.Parse(q.Dequeue()); }
    public static string NextString() { Confirm(); return q.Dequeue(); }
    public static double NextDouble() { Confirm(); return double.Parse(q.Dequeue()); }
    public static int[] LineInt() { return Console.ReadLine().Split(' ').Select(int.Parse).ToArray(); }
    public static long[] LineLong() { return Console.ReadLine().Split(' ').Select(long.Parse).ToArray(); }
    public static string[] LineString() { return Console.ReadLine().Split(' ').ToArray(); }
    public static double[] LineDouble() { return Console.ReadLine().Split(' ').Select(double.Parse).ToArray(); }
}

class Util
{
}




Compiler output:
main.c:1:1: error: unknown type name 'using'
    1 | using System;
      | ^~~~~
main.c:2:1: error: unknown type name 'using'
    2 | using System.Collections.Generic;
      | ^~~~~
main.c:2:13: error: expected '=', ',', ';', 'asm' or '__attribute__' before '.' token
    2 | using System.Collections.Generic;
      |             ^
main.c:3:1: error: unknown type name 'using'
    3 | using System.Linq;
      | ^~~~~
main.c:3:13: error: expected '=', ',', ';', 'asm' or '__attribute__' before '.' token
    3 | using System.Linq;
      |             ^
main.c:4:1: error: unknown type name 'using'
    4 | using System.Text;
      | ^~~~~
main.c:4:13: error: expected '=', ',', ';', 'asm' or '__attribute__' before '.' token
    4 | using System.Text;
      |             ^
main.c:5:1: error: unknown type name 'using'
    5 | using System.Threading.Tasks;
      | ^~~~~
main.c:5:13: error: expected '=', ',', ';', 'asm' or '__attribute__' before '.' token
    5 | using System.Threading.Tasks;
      |             ^
main.c:6:1: error: unknown type name 'using'
    6 | using System.IO;
      | ^~~~~
main.c:6:13: error: expected '=', ',', ';', 'asm' or '__attribute__' before '.' token
    6 | using System.IO;
      |             ^
main.c:8:6: error: expected ';' before 'static'
    8 | using static Input;
      |      ^~~~~~~
      |      ;
main.c:8:14: error: type defaults to 'int' in declaration of 'Input' [-Wimplicit-int]
    8 | using static Input;
      |              ^~~~~
main.c:10:1: error: unknown type name 'class'
   10 | class Program
      | ^~~~~
main.c:11:1: error: expected '=', ',', ';', 'asm' or '__attribute__' before '{' token
   11 | {
      | ^
main.c:45:1: error: unknown type name 'public'
   45 | public class Input
      | ^~~~~~
main.c:45:14: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'Input'
   45 | public class Input
      |              ^~~~~
main.c:61:1: error: unknown type name 'class'
   61 | class Util
      | ^~~~~
main.c:62:1: error: expected '=', ',', ';', 'asm' or '__attribute__' before '{' token
   62 | {
      | ^