Long Distance Racing
題目描述
Bessie is training for her next race by running on a path that includes hills so that she will be prepared for any terrain. She has planned a straight path and wants to run as far as she can – but she must be back to the farm within M seconds (1 ≤ M ≤ 10,000,000).
The entire path she has chosen is T units (1 ≤ T ≤ 100,000) in length and consists of equal-length portions that are uphill, flat, or downhill. The input data describes path segment i with a single character Si that is u, f, or d, indicating respectively uphill, flat, or downhill.
Bessie takes U seconds (1 ≤ U ≤ 100) to run one unit of uphill path, F (1 ≤ F ≤ 100) seconds for a unit of flat path, and D (1 ≤ D ≤ 100) seconds for a unit of downhill path. Note that, when returning home, uphill paths become downhill paths and downhill paths become uphill paths.
Find the farthest distance Bessie can get from the farm and still make it back in time.
Iutput
- Line 1: Five space-separated integers: M, T, U, F, and D
- Lines 2..T+1: Line i+1 describes path segment i with a single letter: Si
Output
- Line 1: A single integer that is the farthest distance (number of units) that Bessie can get from the farm and make it back in time.
Sample Input
13 5 3 2 1
u
f
u
d
f
Sample Output
3
思路：
題意：一段路有上坡路、平路、下坡路，其中上坡對應下坡，各段長度相同，但是所用的時間不同，現在給定一段時間，問能走多遠；
思路：每次根據所剩的時間判斷能否繼續往前走；
代碼
code