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CSharp · Console

/Program.cs

using System;
					
public class Program
{
	public static void Main()
	{
		string mySum = "200+800";
		int totalSum = 0;
		foreach(var op in mySum.Split('+'))
		{
			totalSum += Convert.ToInt16(op);
		}
		Console.WriteLine(totalSum);
	}
}