function solution(s){
var answer = 0;
let arr=[s[0]];
for(let i=1;i<s.length;i++){
arr.push(s[i]);
if(arr[arr.length-1]===arr[arr.length-2]){
arr.pop();
arr.pop();
}
}
if(arr.length===0)answer=1
return answer;
}