What will be it's out put

Question

//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

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

namespace Rextester
{
public class Program
{
public static void Main(string[] args)
{
function add(arr) {
var a arr.reduce(function(p, c) {
return p+c;
});
return a;
}
function multiply(arr, func){
var doubles=arr.map(function(n) {
return n*n;
});
return func(doubles);
}
var m = multiply([1, 2, 31, add);
console.log(m);
}
}
}

Answer 1

Looks like there are 2 languages in this code - C# and JS.
So probably an error 😜