Find longest common subsequence between given two strings. Letter orders must be kept in strings.

longestCommonSubsequence.js

// Top-down without memoization, kind of bruteforce. Time complexity is too bad.
var longestCommonSubsequence = function(text1, text2) {
    if(text1.length===0 || text2.length===0) return 0;
    
    let letter1 = text1[0];
    let firstOccurance = text2.indexOf(letter1);
    let case1 = longestCommonSubsequence(text1.substring(1), text2); 
    // text1 in ilk harfiyle olan kombinasyon cozumun parcasi degilse, ilk harfi haric text1 ile text2 recursive sokulur
    
    let case2=0;
    if(text2.indexOf(letter1)>=0){
        case2 = 1 + longestCommonSubsequence(text1.substring(1),text2.substring(firstOccurance + 1)); 
        // ustteki bag eger cozumun parcasiysa 1+ ilk textin kalan kismi ve o harfin ikinci textteki indeksinden sonraki kisim recursive sokulur  
    }

    return Math.max(case1,case2);
};
console.log(longestCommonSequence("abcde","ace"));