using System;

using System.Text;

​

// increment int in loop

int c = 10;

for (int i = 0; i < 100; ++i)

{

    c += 5;

}

Console.WriteLine("c: {0}", c);

​

// concat string in loop

string acc = "";

for (int i = 0; i < 100; ++i)

{

    acc += "A";

}

Console.WriteLine("acc: {0}", acc);

​

// concat string with StringBuilder

var sb = new StringBuilder();

for (int i = 0; i < 100; ++i)

{

    sb.Append("A");

}

Console.WriteLine("sb: {0}", sb.ToString());

​

​

​