Dima and Staircase
Dima’s got a staircase that consists of n stairs. The first stair is at height a 1, the second one is at a 2, the last one is at a n (1 ≤ a 1 ≤ a 2 ≤ … ≤ a n). Dima decided […]
Staircase
Dima’s got a staircase that consists of n stairs. The first stair is at height a 1, the second one is at a 2, the last one is at a n (1 ≤ a 1 ≤ a 2 ≤ … ≤ a n). Dima decided […]