#include <stdio.h>int main(int argc, const char * argv[]) {    int16_t y = 14, m = 9, d =17;    int16_t data = 0;//y<<9                   //  0000  0000 0000 1110            // 0001 1100 0000 0000(在一年之内, 存储只到2^7, 所以前面9个0就是没意义的, 就缩写成第二个状态)//(m<<12)>>7    //  0000 0001 0010 0000//(d<<11)>>11// 0000 0000 0001 0001        data = (y<<9)|((m<<12)>>7)|((d<<11)>>11);        printf("%02x\n", data);        return 0;}

#include <stdio.h>int main(int argc, const char * argv[]) {    int year;        printf("请输入年份: ");    scanf("%d", &year);        if((0 == year%4)||((0 == year%400)&&(0 != year%100)))    {        printf("是闰年\n");    }    else        printf("不是闰年\n");    return 0;}

////  ViewController.m//  demo2////  Created by apple on 14-9-17.//  Copyright (c) 2014年 apple. All rights reserved.//#import "ViewController.h"@interface ViewController (){    NSString *op1, *op2;    char op;}@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];    op1 = @"";    op2 = @"";    // Do any additional setup after loading the view, typically from a nib.}- (IBAction)button1clicked:(id)sender {    NSLog(@"1 clicked");    if (op != ‘+‘ && op != ‘-‘        && op != ‘*‘ && op != ‘/‘) {        //1231        op1 = [NSString stringWithFormat:@"%@%d", op1,1];    }else    {        op2 = [NSString stringWithFormat:@"%@%d", op2,1];    }}- (IBAction)button2clicked:(id)sender {    NSLog(@"2 clicked");    if (op != ‘+‘ && op != ‘-‘        && op != ‘*‘ && op != ‘/‘) {        //1231        op1 = [NSString stringWithFormat:@"%@%d", op1,1];    }else    {        op2 = [NSString stringWithFormat:@"%@%d", op2,1];    }}- (IBAction)button3clicked:(id)sender {    NSLog(@"3 clicked");    if (op != ‘+‘ && op != ‘-‘        && op != ‘*‘ && op != ‘/‘) {        //1231        op1 = [NSString stringWithFormat:@"%@%d", op1,1];    }else    {        op2 = [NSString stringWithFormat:@"%@%d", op2,1];    }}- (IBAction)add:(id)sender {    op = ‘+‘;}- (IBAction)jieguo:(id)sender {    if (op == ‘+‘) {        //NSString转int整形数值        int a1 = [op1 intValue];        int a2 = [op2 intValue];        int sum = a1 + a2;        NSLog(@"%d", sum);        NSString *result = [NSString stringWithFormat:@"%d", sum];        self.jieguo.text = result;    }}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end