#include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(0);     cin.tie(0);     int k, n;     cin >> k >> n;     int ans = 0;     unordered_set<int> pref_sums;     int curr_sum = 0;     while (k--) {       int x;       cin >> x;       curr_sum += x;       pref_sums.insert(curr_sum);     }     unordered_set<int> r;     while (n--) {       int x;       cin >> x;       r.insert(x);     }     for (int p : pref_sums) {       int i = *begin(r) - p;       bool check = true;       for (int e : r) {         if (!count(pref_sums.begin(), pref_sums.end(), e - i)) {           check = false;           break;         }       }       if (check) ans++;     }     cout << ans <<   n ;   }   