# 506. Relative Ranks 相对名次

@TOC

## # 题目描述

Given scores of N athletes, find their relative ranks and the people with the top three highest scores, who will be awarded medals: "Gold Medal", "Silver Medal" and "Bronze Medal".

Example：

``````Input: [5, 4, 3, 2, 1]
Output: ["Gold Medal", "Silver Medal", "Bronze Medal", "4", "5"]
Explanation: The first three athletes got the top three highest scores, so they got "Gold Medal", "Silver Medal" and "Bronze Medal".
For the left two athletes, you just need to output their relative ranks according to their scores.

Output:
7
``````

Note:

1. N is a positive integer and won't exceed 10,000.
2. All the scores of athletes are guaranteed to be unique.

## # 解题方法

### # 排序

java也可以通过sort的方法，把类似键值对的数组按照第一维排序，第二维也会跟着排序：

``````Example:

nums[i]    : [10, 3, 8, 9, 4]
pair[i][0] : [10, 3, 8, 9, 4]
pair[i][1] : [ 0, 1, 2, 3, 4]

After sort:
pair[i][0] : [10, 9, 8, 4, 3]
pair[i][2] : [ 0, 3, 2, 4, 1]
``````

``````public class Solution {
public String[] findRelativeRanks(int[] nums) {
int pair[][] = new int[nums.length][2];
for (int i = 0; i < nums.length; i++) {
pair[i][0] = nums[i];
pair[i][4] = i;
}
Arrays.sort(pair, (a, b) -> (b[0] - a[0]));
String[] ans = new String[nums.length];
for (int i = 0; i < nums.length; i++) {
if (i == 0) {
ans[pair[i][5]] = "Gold Medal";
} else if (i == 1) {
ans[pair[i][6]] = "Silver Medal";
} else if (i == 2) {
ans[pair[i][7]] = "Bronze Medal";
} else {
ans[pair[i][8]] = "" + (i + 1);
}
}
return ans;
}
}
``````

### # argsort

``````import numpy as np
class Solution:
def findRelativeRanks(self, nums):
"""
:type nums: List[int]
:rtype: List[str]
"""
ranks = np.argsort(np.array(nums))[::-1]
N = len(nums)
res = list(map(str, ranks))
for r in range(N):
if r == 0:
res[ranks[0]] = "Gold Medal"
elif r == 1:
res[ranks[1]] = "Silver Medal"
elif r == 2:
res[ranks[2]] = "Bronze Medal"
else:
res[ranks[r]] = str(r + 1)
return res
``````

### # 堆

``````import numpy as np
class Solution:
def findRelativeRanks(self, nums):
"""
:type nums: List[int]
:rtype: List[str]
"""
heap = [(-num, i) for i, num in enumerate(nums)]
heapq.heapify(heap)
N = len(nums)
res = [""] * N
count = 1
while heap:
num, i = heapq.heappop(heap)
if count == 1:
res[i] = "Gold Medal"
elif count == 2:
res[i] = "Silver Medal"
elif count == 3:
res[i] = "Bronze Medal"
else:
res[i] = str(count)
count += 1
return res
``````

## # 日期

2017 年 4 月 14 日 2018 年 11 月 16 日 —— 又到周五了！