用C++简单实现密码设置与解锁_c++设置密码

要求：

➢设置一个密码，允许数字和字母组合。
➢如果输入字符低于某个数值（比如6或8），提示：密码过短请重试。
➢连续输入3次错误密码，不再允许输入密码。
➢可以选择密码重置，将之前的密码覆盖。
 

实现:

1.设置密码

void SetPassword(char * x)    //此函数用于设置密码
{
	cout << "Please set your password:" << endl;
	cin.getline(x, MAX);    //从键盘输入不超过MAX位的字符作为密码
	if (strlen(x) < MIN)    //判断输入密码长度，MIN为题目要求的密码最短位数
	{
		cout << "The password is too short.";
		SetPassword(x);    //若密码输入过短，会再次要求输入
	}
	else
		cout << "The password is set successfully." << endl;
	cout << "------------------------------" << endl;
}

2.输入密码

void Decipher(char*y)    //此函数用于解开密码
{
	int i;
	char str[MAX];
	cout << "Please enter a password:" << endl;
	for (i = 0; i < 3; i++) {
		cin.getline(str, MAX);    //从键盘输入一串字符
		if (strcmp(y, str) == 0) {    //判断输入字符串和密码是否相同
			cout << "Deciphering successfully!" << endl;
			break;
		}
		else {
			cout << "Please enter your password again and you have "
				<<2-i <<" more chance." << endl;
		}
	}
	cout << "------------------------------" << endl;
}

3.main函数部分

int main()
{
	int a = 0;
	char code[MAX];
	char* p1 = code;
	SetPassword( p1 );
	while (a != 3) {
		cout << "Please choose what you want to do next:" << endl
			<< "1.Reset the password\t2.Unlock the password\t3.Come to an end" << endl;
                //1.重置密码   2.输入密码   3.结束程序
		cin >> a;
		getchar();    //把\n“吸”掉（可以去掉此行，运行程序，来进行对比）
		if (a == 1) {
			SetPassword(p1);
		}
		else if (a == 2) {
			Decipher( p1 );
		}
	}
}

4.总程序

#include <iostream>
#include <string>
#define MIN 6              //限定密码最小长度
#define MAX 100
using namespace std;
 
void SetPassword(char * x)
{
	cout << "Please set your password:" << endl;
	cin.getline(x, MAX);
	if (strlen(x) < MIN)
	{
		cout << "The password is too short.";
		SetPassword(x);
	}
	else
		cout << "The password is set successfully." << endl;
	cout << "------------------------------" << endl;
}
 
void Decipher(char*y)
{
	int i;
	char str[MAX];
	cout << "Please enter a password:" << endl;
	for (i = 0; i < 3; i++) {
		cin.getline(str, MAX);
		if (strcmp(y, str) == 0) {
			cout << "Deciphering successfully!" << endl;
			break;
		}
		else {
			cout << "Please enter your password again and you have "
				<<2-i <<" more chance." << endl;
		}
	}
	cout << "------------------------------" << endl;
}
 
int main()
{
	int a = 0;
	char code[MAX];
	char* p1 = code;
	SetPassword( p1 );
	while (a != 3) {
		cout << "Please choose what you want to do next:" << endl
			<< "1.Reset the password\t2.Unlock the password\t3.Come to an end" << endl;
		cin >> a;
		getchar();
		if (a == 1) {
			SetPassword(p1);
		}
		else if (a == 2) {
			Decipher( p1 );
		}
	}
}

运行结果： 

问题提出： 

 有大佬知道为什么这里会出现两条线吗？QAQ

这学期刚学C++ ，感觉头好痒，要长脑子了ᕦ༼༎ຶ_༎ຶ༽ᕗ