var input = require("fs").readFileSync("/dev/stdin", "utf8").trim().split("\n");
var obj = {
  "list" : input,
  "index" : 0,
  "max" : input.length,
  "next" : function(){
    if(!this.hasNext()){throw "NoSuchElementException:次に要素は無いよ";}
    var returnObj = this.list[this.index];
    this.index++;
    return returnObj;
  },
  "hasNext" : function(){return (this.index < this.max);}
}
Main();
function next(){return obj.next();}
function hasNext(){return obj.hasNext();}
function myout(t){console.log(t);}//standard output
function myerr(t){console.error(t);}//standard error
//[no]要素の扱い。数値型
//不明値、異常時:引数そのまま返す　1:数値へ変換
//2:半角SPで分割 4:半角SPで分割し、数値配列へ
//6:1文字で分割  7:1文字で分割し、数値配列へ
//8:半角SPで結合 9:改行で結合 0:文字なしで結合
function myconv(i,no){try{switch(no){case 1:return parseInt(i);case 2:return i.split(" ");case 4:return i.split(" ").map((a)=>Number(a));case 6:return i.split("");case 7:return i.split("").map((a)=>Number(a));case 8:return i.join(" ");case 9:return i.join("\n");case 0:return i.join("");default:return i;}}catch(e){return i;}}
function Main(){
  var N = myconv(next(),1);
  var list = myconv(next(),4);
  var s = new Array(N + 1);
  s[0] = 0;
  var set = {"0" : 0};
  for(var i = 0; i < N; i++){
    s[i + 1] = s[i] + list[i];
    if(set[s[i + 1]] == null){
       set[s[i + 1]] = 0;
    }else{
       set[s[i + 1]]++;
    }
  }
  var output = 0;
  var keys = Array.from(Object.keys(set));
  for(var i = 0; i < keys.length; i++){
    var tmp = set[keys[i]];
    output += (tmp * (tmp + 1)) / 2;
  }
  myout(output);
}
function gcd(m, n) {return n != 0 ? gcd(n, m % n) : m;}
