*Note: The time limit for this problem is 6s, three times the default. The
memory limit for this problem is 512MB, twice the default.*

Bessie is a hungry cow. Each day, for dinner, if there is a haybale in the barn,
she will eat one haybale. Farmer John does not want Bessie to starve, so some
days he sends a delivery of haybales, which arrive in the morning (before
dinner). In particular, on day \(d_i\), Farmer John sends a delivery of \(b_i\)
haybales (\(1\leq d_i \leq 10^{14}\), \(0\leq b_i \leq 10^9\)).

Process \(U\) (\(1\le U\le 10^5\)) updates as follows: Given a pair \((d, b)\),
update the number of haybales arriving on day \(d\) to \(b\). After each update,
output the sum of all days on which Bessie eats haybales modulo
\(10^9+7\).

Problem credits: Brandon Wang and Benjamin Qi

SCORING

• Input 3: \(U\le 5000\)
• Inputs 4-10: Updates only increase the number of haybales arriving on day \(d\).
• Inputs 11-22: No additional constraints.

Problem credits: Brandon Wang and Benjamin Qi

\(U\), followed by \(U\) lines containing the updates.

The sum after each update modulo \(10^9+7\).

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