Function pull

Range Queries/Subarray Sum Queries.cpp:10–15

ll x, sum[SIZE], dp[SIZE], dpl[SIZE], dpr[SIZE];

void pull(int i){
    dpl[i] = max(dpl[2*i], sum[2*i] + dpl[2*i+1]);
    dpr[i] = max(dpr[2*i+1], sum[2*i+1] + dpr[2*i]);
    dp[i] = max(dpr[2*i] + dpl[2*i+1], max(dp[2*i], dp[2*i+1]));
    sum[i] = sum[2*i] + sum[2*i+1];
}

void build(int i, int l, int r){
    lo[i] = l; hi[i] = r;