7月13日 今日所学 分享整理

#define _CRT_SECURE_NO_WARNINGS 1
#include <string.h>
#include <stdio.h>

int main()
{
	int arr1[10] = {1,2,3};//不完全初始化
	char arr2[5] = { 1, 2, 3, 4, 5 };
	char arr3[] = { 1, 2, 3, 4};
	char arr4[5] = { 1, 2, 3};
	char arr5[3] = { 'a', 4, 'c' };
	char arr6[] = { 'a', 'b', 'c'};
	char arr7[] = "abcdef";
	return 0;

}



int main()
{
	char arr[] = "abcdef";//{ 'a', 'b', 'c', 'd', 'e', 'f' };
	int i = 0;
	for (i = 0; i<strlen(arr); i++)
	{
		printf("%c ", arr[i]);
	}
	return 0;
}



输入一串随机数组，进行打印
int main()
{
	char arr[20] = {0};//"abcdef";//{ 'a', 'b', 'c', 'd', 'e', 'f' };
 	scanf("%s", &arr);
	int i = 0;
	for (i = 0; i<strlen(arr); i++)
	{
		printf("%c ", arr[i]);
	}
	return 0;
}




BUG修改完毕，    账号登录系统1.0
#define _CRT_SECURE_NO_WARNINGS 1
#include <string.h>
#include <stdio.h>

int main()
{

	char accounts[40] = { 0 };
	char password[40] = { 0 };
	int i = 0;
	printf("请输入账号:>");
	scanf("%s", &accounts);
	if (strcmp(accounts, "123456")==0)// && strcmp(accounts, "123") == 0 && strcmp(accounts, "456") == 0)
	{
		printf("登记库中存在\n");
	}

	for (i = 1; i <= 3; i++)
	{
		printf("请输入密码:>");
		scanf("%s", &password);
		if ((strcmp(password, "YG123456") == 0) && (strcmp(accounts, "123456") == 0))//==不能用来比较两个字符串是否相等，应该使用一个库函数-strcmp
		{
			printf("登陆成功\n");
			break;
		}
		else 
		{
			printf("账号不在登记库中，不予登录\n");
			printf("请输入账号:>");
			scanf("%s", &accounts);
		}
		if (i == 3)
		{
			printf("三次均错误，账号已冻结\n");
		}
	}
	return 0;
}


int main()
{
	int arr[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
	int sz = sizeof(arr) / sizeof(arr[0]);
	int i = 0;
	for (i = 1; i < sz; i++)
	{
		printf("arr[%d] = %p\n", i,  &arr[i]);
	}
	return 0;
	
}


int main()
{
	int arr[3][4] = {{1,2,3}, {4,5}};
	int i = 0;
	for (i = 0; i < 3; i++)
	{
		int j = 0;
		for (j = 0; j < 4; j++)
		{
			printf("&arr[%d][%d] = %p\n",  i, j, &arr[i][j]);
		}
	}
	return 0;
}



void bubble_sort(int arr[], int se)
{
	int i = 0;
	for (i = 0; i < se - 1; i++)
	{
		int flag = 1;
		int j = 0;
		for (j = 0; j<se - 1 - i; j++)
		{
			if (arr[j] > arr[j + 1])
			{
				int tmp = arr[j];
				arr[j] = arr[j + 1];
				arr[j + 1] = tmp;
				flag = 0;

			}
		}
		if (flag == 1)
		{
			break;
		}
	}
}





int main()
{
	int arr[] = { 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 };
	int i = 0;
	int se = sizeof(arr) / sizeof(arr[0]);
	bubble_sort(arr, se);
	for (i = 0; i < se; i++)
	{
		printf("%d ", arr[i]);
	}
	return 0;
}