title: Java modulo operator and GCD
body: <p>Why does this code give me an answer of 25?</p>
  
  <pre><code>public int findGcd() {
      int num = this.num;
      int den = this.den;
  
      while (den != 0) {
          int t = den;
          den = num % den;
          num = t;
      }
  
      return num;
  }
  </code></pre>
  
  <p>This is the main method:</p>
  
  <pre><code>public class FractionTest {
      public static void main(String args[]) {
          Fraction f = new Fraction();
          f.num = 25;
          f.den = 100;
          f.findGcd();
      }
  }
  </code></pre>
  
  <p>Can anyone provide me a complete process of how all the program goes or run?</p>