Two string -

Twostring4.js

function processData(input) {
    var lines = input.split("\n").slice(1), a, b, substring;
    for(var i = 0; i < lines.length; i+=2) {
        substring = false;
        a = lines[i];
        b = lines[i+1];
        if(b.length > a.length) {
            a = lines[i+1];
            b = lines[i];
        }
        for(var j = 0; j < a.length; j++) {
            if(b.indexOf(a.charAt(j)) > 0) {
                substring = true;
                break;
            }
        }
        console.log(substring ? "YES" : "NO");
    }
} 

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

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