[为我的班级做练习。我的老师希望我们使用C弦,而不是弦类。我们必须使用布尔函数和C字符串命令来确定密码是否足够强。我想我快要完成了,但是我必须在某个地方犯一些错误?这是我所拥有的:
#include <iostream>
#include <cstring>
#include <cctype>
bool checklength(char[]);
bool checkdigit(char[]);
bool checklower(char[]);
bool checkupper(char[]);
bool checkspecial(char[]);
int main()
{
char pwdstr[20];
std::cout << "Enter your password\n";
std::cin >> pwdstr;
if (checklength(pwdstr) &&
checkdigit(pwdstr) &&
checklower(pwdstr) &&
checkupper(pwdstr) &&
checkspecial(pwdstr))
{
std::cout << "Your password is strong.\n";
}
else
{
std::cout << "Your password is too weak!\n";
}
}
bool checklength(char p[])
{
int i;
int len = strlen(p);
for (i = 0; i < len - 1;)
{
if (isalnum(p[i]))
{
i++;
}
}
if (i < 6)
{
std::cout << "Your password must be at least 6 characters
long.\n";
return false;
}
else
{
return true;
}
}
bool checkdigit(char p[])
{
int i;
int len = strlen(p);
for (i = 0; i < len - 1;)
{
if (isdigit(p[i]))
{
i++;
}
}
if (i < 1)
{
std::cout << "Your password must have at least 1 digit in
it.\n";
return false;
}
else
{
return true;
}
}
bool checklower(char p[])
{
int i;
int len = strlen(p);
for (i = 0; i < len - 1;)
{
if (islower(p[i]))
{
i++;
}
}
if (i < 1)
{
std::cout << "Your password must have at least 1 lower case
letter in it.\n";
return false;
}
else
{
return true;
}
}
bool checkupper(char p[])
{
int i;
int len = strlen(p);
for (i = 0; i < len - 1;)
{
if (isupper(p[i]))
{
i++;
}
}
if (i < 1)
{
std::cout << "Your password must have at least 1 upper case
letter in it.\n";
return false;
}
else
{
return true;
}
}
bool checkspecial(char p[])
{
int i;
int len = strlen(p);
for (i = 0; i < len - 1;)
{
if (ispunct(p[i]))
{
i++;
}
}
if (i < 1)
{
std::cout << "Your password must have at least 1 special
character in it.\n";
return false;
}
else
{
return true;
}
}
在添加错误描述之前,返回false之前的当前输出是,由于某种原因,一切都正确。现在,我尝试的所有内容都表明我在checklength函数上失败,密码太短。
谢谢所有
您的所有循环都是错误的,您正在混淆正在测试的字符的索引,以及通过测试的字符数的计数,为此您需要单独的变量。另外,您在字符串长度的长度上有一个错误,您使用了len - 1
而不是len
。所以这个
bool checklength(char p[])
{
int i;
int len = strlen(p);
for (i = 0; i < len - 1;)
{
if (isalnum(p[i]))
{
i++;
}
}
if (i < 6)
{
std::cout << "Your password must be at least 6 characters long.\n";
return false;
}
else
{
return true;
}
}
应该是这个
bool checklength(char p[])
{
int count = 0;
int len = strlen(p);
for (int i = 0; i < len; i++)
{
if (isalnum(p[i]))
count++;
}
if (count < 6)
{
std::cout << "Your password must be at least 6 characters long.\n";
return false;
}
else
{
return true;
}
}
使用STL算法可以大大简化您的功能。例如checklength
可能是:
bool checklength(char p[])
{
return std::count_if(p, p + strlen(p), [](unsigned char c) {
return std::isalnum(c);
}) >= 6;
}
并且您可以为其他功能做类似的事情。