Hungry Cow timer 6s memory 512MB

**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 di, Farmer John sends a delivery of bi haybales (1≤di≤10¹⁴, 0≤bi≤10⁹).

Process U (1≤U≤10⁵) 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 10⁹+7.​