U5v82S - Online C++0x Compiler & Debugging Tool

#include <bits/stdc++.h>
using namespace std;
#define int              long long int
#define double           long double
#define print(a)         for(auto x : a) cout << x << " "; cout << endl


const int M = 1000000007;
const int N = 3e5+9;
const int INF = 2e9+1;
const int LINF = 2000000000000000001;

inline int power(int a, int b, int mod=M) {
    int x = 1;
    a %= mod;
    while (b) {
        if (b & 1) x = (x * a) % mod;
        a = (a * a) % mod;
        b >>= 1;
    }
    return x;
}


//_ ***************************** START Below *******************************

// 9 1 3
// 1 0 1 1 0 1 0 1 1


vector<int> a;

int consistency(int n, int x, int y){

	unordered_map<int,int> mp = {{0, 1}};

	int ans = 0;

	int zero = 0;
	int one = 0;

	for(int i=0; i<n; i++){
		if(a[i] == 1) one++;
		else zero++;

		int val = y*zero - x*one;

		if(mp.count(val)){
			ans += mp[val];
		}

		mp[val]++;

	}

	return ans;
}


int practice(int n, int x, int y){


    return 0;
}


void solve() {

    int n, x, y;
    cin>> n >> x >> y;

    a.resize(n);
    for(int i=0; i<n; i++) cin >> a[i];

    cout << consistency(n, x, y) << endl;


}


int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}