LESSON 165 OF 409 · PROJECTS: EVERYDAY PROGRAMS

Password Strength V3 - Character Classes in C++

Practice

Track four boolean flags for a password: does it contain an uppercase letter, a lowercase letter, a digit, and a symbol (non-alphanumeric)?

You start with:

string password = "Secret!99";

Build:

Length: 9
Upper: True
Lower: True
Digit: True
Symbol: True
Strong

Rules:

Print "Length: " followed by the number of characters.
Start four flags (hasUpper, hasLower, hasDigit, hasSymbol) at false. Loop over every character and set the matching flag to true.
A symbol is any character that is not a letter and not a digit.
Print one line per flag, in this order: "Upper: ", "Lower: ", "Digit: ", "Symbol: ", each followed by the flag. Write it as True or False with a capital letter, exactly as in the example (your language's own boolean prints differently, so choose the text yourself).
If the length is at least 8 and all four flags are true (stricter than the last lesson), print Strong; otherwise print Weak.

Try other passwords: with secret99 the output is

Length: 8
Upper: False
Lower: True
Digit: True
Symbol: False
Weak

Use isupper, islower, isdigit, isalnum from <cctype>.

string password = "Secret!99";

int length = password.length();
cout << "Length: " << length << endl;
bool hasUpper = false;
bool hasLower = false;
bool hasDigit = false;
bool hasSymbol = false;
for (char c : password) {
    if (isupper(c)) {
        hasUpper = true;
    }
    if (islower(c)) {
        hasLower = true;
    }
    if (isdigit(c)) {
        hasDigit = true;
    }
    if (!isalnum(c)) {
        hasSymbol = true;
    }
}
cout << "Upper: " << (hasUpper ? "True" : "False") << endl;
cout << "Lower: " << (hasLower ? "True" : "False") << endl;
cout << "Digit: " << (hasDigit ? "True" : "False") << endl;
cout << "Symbol: " << (hasSymbol ? "True" : "False") << endl;
if (length >= 8 && hasUpper && hasLower && hasDigit && hasSymbol) {
    cout << "Strong" << endl;
} else {
    cout << "Weak" << endl;
}

STEP 1 OF 13

Guided

Ctrl + Enter to check

Password Strength V3 - Character Classes in C++

Password Strength V3 in C++