#include <bits/stdc++.h>
using namespace std;
using T = long long;
T calc(T sum, T ls, T ai) { return abs(abs(ls - (sum - ls - ai)) - ai%2); }
int main() {
	int n, q, p = 0;
	cin >> n >> q;
	vector<int> a(n);
	T sum = 0, ls = 0;
	for(int i = 0; i < n; ++i) {
		cin >> a[i];
		sum += a[i];
	}
	while(q--) {
		int i, x;
		cin >> i >> x;
		T d = x - a[i];
		sum += d;
		a[i] = x;
		if(i < p) ls += d;
		pair<T, int> best = {calc(sum, ls, a[p]), p};
		while(ls < sum - ls - a[p] && p < n - 1) {
			ls += a[p++];
			best = min(best, {calc(sum, ls, a[p]), p});
		}
		while(ls > sum - ls - a[p] && p > 0) {
			ls -= a[--p];
			best = min(best, {calc(sum, ls, a[p]), p});
		}
		while(p < best.second) ls += a[p++];
		while(p > best.second) ls -= a[--p];
		cout << best.second << '\n';
	}
	return 0;
}