All combos 3, DFS, mine

var str = "abcde";
var length = str.length;
var conterIndx = 0;
var result = [];

debugger;

var processStr = function(str, idx) {
    if(idx == str.length) {
        return;
    }
    var char = str.charAt(idx);
    var tempArr =  [char];
    for(var res in result) {
        tempArr.push("" + result[res] + char);
    }
    result = result.concat(tempArr);
    idx++;
    processStr(str, idx);
    return result;
}

var res = processStr(str, conterIndx);
console.log(res);