JavaScript_ replace char / word

function solve(firstWord, missingChar, secondWord) {
    let newWord = "";

    for (let i = 0; i < firstWord.length; i++) {

        if (firstWord[i] === '_') {
            newWord += missingChar;
        } else {
            newWord += firstWord[i];
        }
    }

    if (newWord == secondWord) {
        console.log("Matched");
    } else {
        console.log("Not Matched");
    }


}
solve('Str_ng', 'I', 'Strong');


/* You will receive 3 parameters (string, char, string).
The first string will be a word with a missing char replaced with an underscore '_'
You have to replace the character with the missing part (underscore)
from the first string and compare the result with the second string.
If they are equals you should print "Matched", otherwise print "Not Matched".
*/