////  main.m//  NSNumber数字的使用////  Created by on 14-10-5.//  Copyright (c) 2014年 apple. All rights reserved.//#import 
    
     int main(int argc, const char * argv[]) {    @autoreleasepool {//        使用NSNumber为基本数据类型进行封装        NSNumber *monthNumber = [NSNumber numberWithInt:10];        NSNumber *lengthNumber = [NSNumber numberWithFloat:10.8];        NSLog(@"month = %@", monthNumber);        NSLog(@"lengthNumber = %@", lengthNumber);        //        还原成基本数据类型        int month = [monthNumber intValue];        float length = [lengthNumber floatValue];        NSLog(@"month = %d", month);        NSLog(@"length = %.2f", length);    }    return 0;}