Javascript Codewars Challenge(isMerge)

Question

I have asked this question before (the first link to my question) but couldn\'t get the complete solution for the question. Write an algorithm to check if a given string, s, can

Answer 1

Here is a non-recursive approach.

function checkIt (str, str1, str2){
    if(str.length !== str1.length + str2.length){
        return false;
    }

    var str1_index = -1
    var str2_index = -1;
    var curr_index1, curr_index2;

    for(var i=0; i str1_index){
            str1_index = curr_index1;
        }
        else if(curr_index1 !== -1 && curr_index1 < str1_index) {
            return false;
        }

        if(curr_index2 > str2_index){
            str2_index = curr_index2;
        }
        else if(curr_index2 !== -1 && curr_index2 < str2_index) {
            return false;
        }   
    }
    return true;
}


console.log(checkIt('codewars', 'cdw', 'oears')); // true
console.log(checkIt('codewars', 'cdw', 'ears'));  // false
console.log(checkIt('codewars', 'cwd', 'oears')); // false
console.log(checkIt('codewars', 'cdw', 'oeasr')); // false