Binary gap

index.js

//Find longest sequence of zeros in binary representation of an integer.

function solution(n) {
    var str = toBinaryString(n).replace(/0+$/, "");
    var arr = str.split("1").filter(function(e) { return e.length > 0; });
    if (arr.length === 0){
      return 0;
    }
    arr.sort(function(a, b){ return b.length - a.length; });
    
    return arr[0].length;
}

function solution2(n) {
    //get binary string
    var str = toBinaryString(n);
    console.log(str);
    
    var re = /(0+?)1/g;
    var ex;
    var result = [];
  
    //find groups
    while (ex = re.exec(str)){
      //console.log(ex[1]);
      result.push(ex[1]);
    }
  
    if (!result.length){
      return 0; 
    }
  
    //sort groups descending
    result.sort().reverse();
  
    return result[0].length;
}

console.log(solution2(41104)); //1010000010010000 - 5
console.log(solution2(127));   //1111111 - 0

function toBinaryString(n){
    return (n >>> 0).toString(2);
}