title: Stroustrup's C++ Book Challenge, Can someone help me understand this code?
body: <p>I saw this code from the Stroustrup's book, but I can't understand how it works.
  I just can't get how it increases by " 0, 1, 4, 9..."</p>
  
  <pre><code>int archaic_square(int v) {
      int total = 0;
  
      for (int i = 0; i &lt; v; ++i) {
          total += v;
      }
      return total;
  }
  
  int main() {
      for (int i = 0; i &lt; 100; ++i) {
          cout &lt;&lt; i &lt;&lt; '\t' &lt;&lt; archaic_square(i) &lt;&lt; '\n';
      }
      return 0;
  }
  </code></pre>