#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
//---------------------------------------计算n的阶乘
//int main()
//{
//  int n = 0;
//  int num = 0;
//  int ret = 1;
//    scanf("%d", &n);
//    for (num = 1; num <= n; num++)
//    {
//      ret = ret * num;
//    }
//
//ntf("%d\n", i);
//  return 0;
//}
//---------------------------------------计算1~n的阶乘和
//int main()
//{
//  int n = 0;
//  int num = 0;
//    int ret = 1;
//  int sum = 0;
//  scanf("%d", &n);
//  for (num = 1; num <= n; num++)
//  {
//    ret *= num;
//    sum += ret;
//  }
//  printf("%d", sum);
//  return 0;
//}
int main()
{
  int arr[] = { 1,2,3,4,5,6,7,8,9,10 };
  int k = 7;
  int az = sizeof(arr) / sizeof(arr[0]);
  int left = 0;
  int light = az - 1;
  while (left<=light)
  {
    int mid = (light + left) / 2;
    if (arr[mid] < k)
    {
      left = mid ;
    }
    else if (arr[mid] > k)
    {
      light = mid;
    }
    else
    {
      printf("%d", mid);
      break;
    }
  };
  return 0;
}
#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<Windows.h>
//编写代码,演示多个字符从两端移动,向中间汇聚。
int main()
{
    char arr1[] = "wolegequa nizrhede niubi";
    char arr2[] = "########################";
    int left = 0;
    int right = strlen(arr1) - 1;
    while (left<=right)
    {
    
        arr2[left] = arr1[left];
        arr2[right] = arr1[right];
        left++;
        right--;
        Sleep(1000);//睡眠1秒
    system("cls");//清空屏幕
        printf("%s\n", arr2);
    
    }
    return 0;
}
#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<Windows.h>
int main()
{
  char arr1[] = "周芬你真的是个人才";
  char arr2[] = "##################";
  int left = 0;
  int right = strlen(arr1) - 1;
  while (left<=right)
  {
  
    arr2[left] = arr1[left];
    arr2[left + 1] = arr1[left + 1];
    left=left+2;
    
    Sleep(1000);//睡眠1秒
    system("cls");//清空屏幕
    printf("%s\n", arr2);
  
  }
  return 0;
}
#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<Windows.h>
#include<string.h>
//---------------------------------------------------
//编写代码实现,模拟用户登录情景,并且只能登录三次(只允许输入三次密码,如果密码正确
//则提示密码输入成功,如果三次都输入错误,则退出程序)。
//----------------------------------------------------
int main()
{
  
  printf("请输入密码\n");
  char arr1[] = "abc123";
  char arr2[20] = "12345678";
  int i = 3;
  while (i > 0)
  {
    scanf("%s", arr2);
    if (strcmp(arr1, arr2) == 0)
    {
      printf("登录成功");
      break;
    }
    
    else
    {
      printf("密码错误请再次输入");
      printf("%d\n", i);
    }
    i--;
    }
  
  return 0;
}