iOS 相同字符串地址

    NSArray *helloWorld = @[@"world",@"hello"];
    NSString *hello_Constant = @"hello";
    NSString *helloFConstant = [NSString stringWithFormat:@"hello"];
    NSString *helloFormate1  = [NSString stringWithFormat:@"%@",hello_Constant];
    NSString *helloFormate2  =[NSString stringWithFormat:@"%@llo",@"he"];