HackerRank Python Find the Runner-Up Score! 解法

# Problem

Given the participants' score sheet for your University Sports Day, you are required to find the runner-up score. You are given n scores. Store them in a list and find the score of the runner-up.

# Input Format

The first line contains n. The second line contains an array A[ ] of n integers each separated by a space.

# Constraints

• 2 <= n <= 10
• -100 <= A[i] <= 100

# Output Format

Print the runner-up score.

# Sample Input

5
2 3 6 6 5

# Sample Output

5

# Explanation 0

Given list is [2, 3, 6, 6, 5 ]. The maximum score is 6, second maximum is 5.
Hence, we print 5 as the runner-up score.

# Answer

這題的題目是 輸入二個變數 n 及 arr
n 用來限制 arr 裡面有幾個值，arr 則是給定數個數字（中間用空格隔開），最後要輸出 arr 中第二大的數字（runner-up）

下面我們用 n 輸入 5，arr 輸入 2 3 6 6 5 2 3 來舉例：

# Source Code

if __name__ == '__main__':
    n = int(input())
    arr = map(int, input().split())

    # Write your code below :

    # 首先，先將 arr 轉為 list 型態，並在後面加上 [:n] 來限制 arr 的長度為我們所輸入的 n
    arrList = list(arr)[:n]
    
    # 取得目前 arrList 中最大的數字
    maxNumber = max(arrList) # 這時 maxNumber 會是 6

    # 若 arrList 有 6 的話，則移除
    while (maxNumber in arrList):
        arrList.remove(maxNumber)

    # 執行完 while 後，arrList 會變成 2 3 5 2 3 （所有的 6 都已被移除）
    # 這時在用 max 取出 arrList 中最大的數，即可得到原先 arrList 中，第二大的數字（runner-up），也就是 5
    runnerUp = max(arrList)
    print(runnerUp)