LESSON 167 OF 410 · PROJECTS: EVERYDAY PROGRAMS

Password Strength V4 - Count Character Classes in JavaScript

Practice

Count how many characters of each class the password contains.

You start with:

const password = "Hello!World9";

Build:

Uppercase: 2
Lowercase: 8
Digits: 1
Symbols: 1

Rules:

Use four integer counters, all starting at 0.
Loop through each character and add 1 to the matching counter.
Treat any character that is not a letter and not a digit as a symbol.
Print one line per counter, in this order: "Uppercase: ", "Lowercase: ", "Digits: ", "Symbols: ", each followed by the count.

Try other passwords: with Pass word!2 the output is

Uppercase: 1
Lowercase: 7
Digits: 1
Symbols: 2

Use uppercase++, etc. to increment integer counters.

const password = "Hello!World9";

let uppercase = 0;
let lowercase = 0;
let digits = 0;
let symbols = 0;
for (const c of password) {
    if (/[A-Z]/.test(c)) {
        uppercase++;
    }
    if (/[a-z]/.test(c)) {
        lowercase++;
    }
    if (/[0-9]/.test(c)) {
        digits++;
    }
    if (!/[A-Za-z0-9]/.test(c)) {
        symbols++;
    }
}
console.log("Uppercase: " + uppercase);
console.log("Lowercase: " + lowercase);
console.log("Digits: " + digits);
console.log("Symbols: " + symbols);

STEP 1 OF 13

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Password Strength V4 - Count Character Classes in JavaScript

Password Strength V4 in JavaScript