I wrote this recursive solution that is quite nice, but I am getting runtime errors on tests 12, 13, 14. Can someone spot the issue? I've noticed one of the misidentified examples was:

1 hHhAhhcahhacaccacccahhchhcHcahaahhchhhchaachcaCchhchcaccccchhhcaahhhhcaacchccCaahhaahachhacaahhaachhhaaaCalhhchaccaAahHcchcazhachhhaaahaahhaacchAahccacahahhcHhccahaachAchahacaahcahacaahcahacaHhccccaahaahacaachcchhahhacchahhhaahcacacachhahchcaAhhcaahchHhhaacHcacahaccccaaahacCHhChchhhahhchcahaaCccccahhcaachhhacaaahcaaaccccaacaaHachaahcchaahhchhhcahahahhcaachhchacahhahahahAahaAcchahaahcaaaaahhChacahcacachacahcchHcaahchhcahaachnachhhhcachchahhhacHhCcaHhhhcaCccccaaahcahacahchahcaachcchaachahhhhhhhhcahhacacCcchahccaaaaaHhhccaAaaaCchahhccaahhacaccchhcahhcahaahhgacahcahhchcaaAccchahhhaahhccaaHcchaccacahHahChachhcaaacAhacacaacacchhchchacchchcacchachacaahachccchhhaccahcacchaccaahaaaccccccaaaaaaaHhcahcchmcHchcchaaahaccchaaachchHahcaccaaccahcacacahAhaacaacaccaccaaacahhhcacAhaCchcaacCcccachhchchcchhchahchchahchchhchcacaachahhccacachaAhaaachchhchchchhaachahaahahachhaaaccacahhcacchhhaaachaaacAahhcachchachhhcacchacaaChCahhhccahChaachhcahacchanaaacchhhccacacchcahccchAcahacaaachhacchachccaaHacaacAhahcCh HAHHCHAACCCAHCHHAHHAHCACCHCCHHCAAHHCACCCAHHHACAAHHHHCHHCAHHAHHAAAHAACAAHAHHCAHAHACHACHCHACACHAAHHAAAHCAHHACACAACHHHCHAHCAHCHHHAHAHACCAAAHCHHCHHCCAACCCCAACHACAACAAHACHCHAHHACCHCAHHHAAACHACAACHCACACAHHCCHAHACCCACCAACHCHHHCCCCCHCCAHHCAAHHAHHHHHHHAACCCCAHCCAAAAAHHHAAAACCAHHCAHACACCHHCHAHAHHCHAACHHHHHCCHCCAHAHCHCAAACCACCCCHACCACHHACHHACACHACCAACCCCAAAAHHAHCHHHCCAHCCHACHHAHCCACACCHAHAAACACCCCAHCCAHACCCCCCHCCHHCHHHHCHCHCAHHHACHAHAACCCAAAACHAACAAAHHAAHAAAHACHHCACHCCHCHAACHACACHHCCCCCAHCACHAAAHCHCAHACAAC

If you try runnning this code with that custom example, you will get a runtime error. I can't figure out what it is because every thing seems to be running as expected when I add print statements. Although, the runtime error occurs in one of the first few recursive calls.

# Recursive helper function for abbreviation
def helper(a:str, b:str, n:int, m:int, res:str = '') -> str:
    
    # if we have reached the end of a, return "YES" if our result equals our target, b
    #       else return "NO"
    if n == len(a): return "YES" if res == b else "NO"
    
    # if index pointer for b is less than its length, recursively add parts of a
    if m < len(b):
        
        # if the current result string is not equal to b up until this moment, return "NO"
        if res != b[:m]: return "NO"
        
        # get the uppercase version of the current letter in a
        up = a[n].upper()
        
        # if value in a is capitalized, add it to the result string, and increase the index pointers
        #   return whether or not the substring a[n+1:] is an abbreviation
        if a[n].isupper(): return helper(a, b, n+1, m+1, res + a[n])
    
        # else if the upper case version equals the current character in b, 
        #   return result of two cases:
        #       1. add the upper cased value to result and increment the index pointers
        #       2. skip this value in a and try using the next value for comparing with b    
        elif up == b[m]: return "YES" if any(result == "YES" for result in [helper(a,b, n+1, m+1, res + up), helper(a,b, n+1, m, res)]) else "NO"
    
    # else if we have reached the end of b, only continue adding characters of a if they are
    #  already capitalized
    elif a[n].isupper(): return helper(a, b, n+1, m, res + a[n])
    
    # if we have reached the end of b and current pointer of is not a capital, keep moving pointer
    #  of a to the right
    return helper(a,b, n+1, m, res)

WHY?????

function abbreviation(a, b) {
    // Write your code here
    const arrA = a.split('');
    const arrB = b.split('');
    let newArr = [];

    function isLowerCase(text) {
        return text === text.toLowerCase() && text !== text.toUpperCase();
    }

    for (let i = 0; i < arrA.length; i++) {
        for (let j = 0; j <= arrB.length; j++) {
            if(!isLowerCase(arrA[i])){
                newArr.push(arrA[i]);
                break
            }
            if(isLowerCase(arrA[i])){
                arrA[i].toUpperCase() === arrB[j] && newArr.push(arrB[j]);
            }
        }
    }
    console.log(newArr)
    for (let i = 0; i < newArr.length; i++) {
        if (arrB[i] !== newArr[i]) {
            return 'NO'
            break
        }
    }
    return 'YES'
}

A top down DP solution:

static int mat[][];

public static boolean canAbbreviate(String a, String b, int n, int m, int[][] mat) {
    if(m == 0)
        return true;
    if(n == 0 && m > 0)
        return false;
    if(mat[n][m] != -1) {
        return mat[n][m] == 1 ? true : false;
    }

    if(a.charAt(n-1) == b.charAt(m-1)) {
        mat[n-1][m-1] = canAbbreviate(a, b, n-1, m-1, mat) == true ? 1 : 0;
        return mat[n-1][m-1] == 1 ? true : false;
    }
    //upperCase n-1 character in string a it and check if equal
    //recur as in first condition otherwise remove it
    char c = a.charAt(n-1);
    String up = c+"";
    up = up.toUpperCase();
    char cu = up.charAt(0);
    if(cu == b.charAt(m-1)) {
        mat[n-1][m-1] = canAbbreviate(a, b, n-1, m-1, mat) == true ? 1 : 0;
        mat[n-1][m] = canAbbreviate(a, b, n-1, m, mat) == true ? 1 : 0;
        return mat[n-1][m-1] == 1 || mat[n-1][m] == 1 ? true : false;
    }
    //check if already is capital then return false
    String s = c+"";
    String s2 = c+"";
    s2 = s2.toLowerCase();
    if(!s.equals(s2)) return false;
    else {
        //remove it as it is not capital
        mat[n-1][m] = canAbbreviate(a, b, n-1, m, mat) == true ? 1 : 0;
        return mat[n-1][m] == 1 ? true: false;
    }
}

public static String abbreviation(String a, String b) {
    // Write your code here
    if(!isAllCharactersPresent(b.toLowerCase(), a.toLowerCase()))
        return "NO";
    mat = new int[a.length()+1][b.length()+1];

    for(int i=0; i < mat.length; i++) {
        Arrays.fill(mat[i], -1);
    }

    return canAbbreviate(a, b, a.length(), b.length(), mat) ? "YES" : "NO";
}

public static boolean isAllCharactersPresent(String b, String a){
    boolean[] aArr = new boolean[26];
    for(char c : a.toCharArray()){
        aArr[c - 'a'] = true;
    }
    for(char c : b.toCharArray()){
        if(aArr[c - 'a'] == false) return false;
    }
    return true;
}

can anyone tell what am i missing?

def match(a, b, i1, i2, ans):

# base case if len(a) < len(b): return False

if i2 >= len(b): # if i1 == len(a) and i2 >= len(b) : ans[0] = True return True

if i1 >= len(a) : return False

c1 = False
c2 = False
c3 = False

# match if a[i1] == b[i2] : c1 = match(a, b, i1 + 1, i2 + 1, ans)

# if small and same char if a[i1].upper() == b[i2] : c2 = match(a, b, i1 + 1, i2 + 1, ans)

# do not match

if a[i1].islower() : c3 = match(a, b, i1+1, i2, ans)

# if c1 == False and c2 == False and c3 == False :

return

def abbreviation(a, b): # Write your code here ans = [False] match(a, b, 0, 0, ans) if ans[0] == True : return 'YES' return 'NO'