title: Sort NSMutableArray
body: <p>please help me
  I want to sort NSMutableArray and yes I can do this by</p>
  
  <pre><code>NSSortDescriptor *sortPoint = [[NSSortDescriptor alloc] initWithKey:@"point" ascending:YES];
  [hightScore sortUsingDescriptors:[NSArray arrayWithObject:sortPoint]];
  </code></pre>
  
  <p>but in NSMuatableArray(hightScore), I have 2 NSMutableDictionary like this</p>
  
  <pre><code>[item setObject:@"player_name" forKey:@"name"];
  [item setObject:@"100" forKey:@"point"];
  </code></pre>
  
  <p>and when I sort by keyword "point" that is string it give me like this
  100 > 20 > 30 > 50
  instead should be
  20 > 30 > 50 > 100</p>
  
  <p>have any idea pleassss.</p>