1#include <stdio.h>
2#include <stdlib.h>
3
4int cmpfunc (const void * a, const void * b) {
5   return ( *(int*)a - *(int*)b );
6}
7
8int* arrayRankTransform(int* arr, int arrSize, int* returnSize) {
9    *returnSize = arrSize;
10    if (arrSize == 0) return NULL;
11
12    int* sorted = (int*)malloc(arrSize * sizeof(int));
13    for (int i = 0; i < arrSize; i++) sorted[i] = arr[i];
14    qsort(sorted, arrSize, sizeof(int), cmpfunc);
15
16    int* rankMap = (int*)malloc(arrSize * sizeof(int));
17    int rank = 1;
18    rankMap[0] = sorted[0];
19    int rankArr[1] = {rank};
20
21    for (int i = 1; i < arrSize; i++) {
22        if (sorted[i] != sorted[i - 1]) {
23            rank++;
24        }
25        rankArr[rank] = sorted[i];
26    }
27
28    int* result = (int*)malloc(arrSize * sizeof(int));
29    for (int i = 0; i < arrSize; i++) {
30        for (int j = 0; j < rank; j++) {
31            if (arr[i] == rankMap[j]) {
32                result[i] = j + 1;
33                break;
34            }
35        }
36    }
37
38    free(sorted);
39    free(rankMap);
40    return result;
41}

1#include <vector>
2#include <unordered_map>
3#include <algorithm>
4using namespace std;
5
vector<int> arrayRankTransform(vector<int>& arr) {
    vector<int> sorted = arr;
    sort(sorted.begin(), sorted.end());

    unordered_map<int, int> rankMap;
    int rank = 1;
    for (int num : sorted) {
        if (!rankMap.count(num)) {
            rankMap[num] = rank++;
        }
    }

    vector<int> result(arr.size());
    transform(arr.begin(), arr.end(), result.begin(), [&rankMap](int num) { return rankMap[num]; });
    return result;
}