iphone UITableView

Controller : UITableViewController<UITableViewDataSource,UITableViewDelegate>

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    // Return the number of sections.
    return [self.singers count];
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{

    return [self.singerSex objectAtIndex:section] ;

}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.
    return [[self.singers objectAtIndex:section] count] ;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    
    // Configure the cell...
    
    
    if(cell == nil){
    
        cell=[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
        
    }
    
    NSInteger section = [indexPath section];
    NSInteger row = [indexPath row];
    cell.textLabel.text = [[self.singers objectAtIndex:section] objectAtIndex:row];
    
    
    return cell;
}

// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        // Delete the row from the data source
        [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
    }   
    else if (editingStyle == UITableViewCellEditingStyleInsert) {
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
    }   
}

#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSInteger section = [indexPath section];
    NSInteger row = [indexPath row];
    //[self performSegueWithIdentifier:[[self.singers objectAtIndex:section] objectAtIndex:row] sender:nil];
    [self performSegueWithIdentifier:@" " sender:[[self.singers objectAtIndex:section] objectAtIndex:row]];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
 Cell。。。