Two string - JavaScript - binary search tree, Math.round

Twostring14.js

function processData(input) {
    
    function parse(str) {
        return parseInt(str, 10);
    }
    
    var lines = input.split('\n');
    
    var length = parse(lines.shift());
    
    for (var i = 0; i < length; i++) {
        console.log(testCase(lines));
    }
} 

function testCase(lines) {
    var a = lines.shift();
    var b = lines.shift();
    
    for (var i = 0; i < a.length; i++) {
        var char = a.charAt(i);
        
        if (binarySearch(b, char, 0, b.length - 1)) {
            return 'YES';
        }
    }
    
    return 'NO';
}

function binarySearch(str, char, start, end) {
    if (start > end) {
        return false;
    }
    
    var middle = Math.round((start + end) / 2);
    var midValue = str.charAt(middle);
    
    if (midValue === char) {
        return true;
    }
    
    if (char > midValue) {
        return binarySearch(str, char, middle + 1, end);
    }
    else {
        return binarySearch(str, char, start, middle - 1);
    }
}

process.stdin.resume();
process.stdin.setEncoding("ascii");
_input = "";
process.stdin.on("data", function (input) {
    _input += input;
});

process.stdin.on("end", function () {
   processData(_input);
});