case-of-zero-one.cpp

#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define ull unsigned long long
#define ff first
#define ss second
#define mp make_pair
#define pb push_back

const int N = 2e5 + 11;

void solve() {
	int n;
	cin >> n;
	string s;
	cin >> s;
	int zero = 0;

	for (int i = 0; i < n; i++)
		if(s[i]=='0')
			zero++;
	cout<< n - 2 * min(zero, n-zero) <<endl;
}

int main() {
	ios_base::sync_with_stdio(false);
    cin.tie(0);
	freopen("input.txt", "r", stdin);
    int no_of_test_cases = 1;
	// cin >> no_of_test_cases;
    while (no_of_test_cases--) execute(); 
	return 0;
}