Amusement Park

N children are waiting in one line for one-seat rides. The park has M rides numbered from 1 to M.

Each ride has a fixed duration. When that many minutes have passed, the child on the ride gets off and the ride immediately becomes empty. Whenever a ride is empty, the child at the front of the line boards it. If multiple rides become empty at the same time, children board them in increasing ride-number order.

Initially all rides are empty, and at minute 0 the first children board the available rides. Determine the number of the ride boarded by the last child in line.

The first line contains the number of children N and the number of rides M, separated by a space. (1 <= N <= 2,000,000,000, 1 <= M <= 10,000)

The second line contains M natural numbers in order, where the ith number is the duration of ride i. Each duration is between 1 and 30 inclusive, and the unit is minutes.

Print the number of the ride boarded by the last child.