SumeSecv

#include <bits/stdc++.h>
using namespace std;
const int nmax = 100006;
int block[nmax], blockSize, a[nmax], N, M;
long long sumByBlock[nmax];

long long getSum(int L, int R) {
	long long ans = 0;
	while(L < R && block[L] == block[L + 1]) {
		ans += a[L];
		L++;
	}
	while(R > L && block[R] == block[R - 1]) {
		ans += a[R];
		R--;
	}
	if(L == R) {
		ans += a[L];
		L++;
	} else {
		ans += a[L];
		ans += a[R];
		L++;
		R--;
	}
	if(L <= R) {
		for(int j = block[L]; j <= block[R]; ++j) {
			ans += sumByBlock[j];
		}
	}
	return ans;
}

void updatePos(int pos, int x) {
	int whatBlock = block[pos];
	sumByBlock[whatBlock] -= a[pos];
	a[pos] = x;
	sumByBlock[whatBlock] += a[pos];
}

int main()  {
    cin >> N;
    for(int i = 0; i < N; ++i) {
        cin >> a[i];
    }
    blockSize = (int) sqrt(N);
    for(int i = 0; i < N; ++i) {
        block[i] = i / blockSize;
    }
    for(int i = 0; i < N; ++i) {
        int whatBlock = block[i];
        sumByBlock[whatBlock] += a[i];
    }
    cin >> M;
    long long ans = -2e18;
    for(int i = 0; i < M; ++i) {
         int L, R;
         cin >> L >> R;
         if(L > R) {
			swap(L, R);
		 }
         ans = max(ans, getSum(L - 1, R - 1));
    }
    cout << ans << '\n';
}