Problem:
Score : 100 points

Problem Statement

Compute A \times B.

Constraints

1 \leq A \leq 100

1 \leq B \leq 100

All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B

Output

Print the value A \times B as an integer.

Sample Input 1

2 5

Sample Output 1

10

We have 2 \times 5 = 10.

Sample Input 2

100 100

Sample Output 2

10000

Solution in C# (.NET Core 3.1.201) (judge verdict: Runtime Error)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ABC169B
{
    class Program
    {
        static void Main(string[] args)
        {
            int N = int.Parse(Console.ReadLine().Trim());
            List<ulong> x = new List<ulong>();
            var t = Console.ReadLine().Trim().Split(' ');
            for(int i=0;i<N;i++) {
                x.Add(ulong.Parse(t[i]));
                if(ulong.Parse(t[i]) == 0) {Console.WriteLine("0"); return; }
            }
            ulong c = 1ul;
            double c2 = 0.0;
            foreach(var k in x ){
                c *= k;
                c2 += Math.Log10((double)k);
                if(c2 > 18.0 || c > 1000000000000000000ul) {Console.WriteLine("-1"); return; }
            }
            Console.WriteLine(c);
//            Console.WriteLine(c2);
        }
    }
}