P17082 [GeeksforGeeks] Largest number in k swaps 1587115620
普及
题目描述

Given a number K and string str of digits denoting a positive integer, build the largest number possible by performing swap operations on the digits of str at most K times.
Example 1:
Input:
K = 4
str = "1234567"
Output:
7654321
Explanation:
Three swaps can make the
input 1234567 to 7654321, swapping 1
with 7, 2 with 6 and finally 3 with 5
Example 2:
Input:
K = 3
str = "3435335"
Output:
5543333
Explanation:
Three swaps can make the input
3435335 to 5543333, swapping 3
with 5, 4 with 5 and finally 3 with 4
Your task:
You don't have to read input or print anything. Your task is to complete the function findMaximumNum() which takes the string and an integer as input and returns a string containing the largest number formed by perfoming the swap operation at most k times.
Expected Time Complexity: O(n!/(n-k)!) , where n = length of input string
Expected Auxiliary Space: O(n)
Constraints:
1 ≤ |str| ≤ 30
1 ≤ K ≤ 10

输入格式

见题面

输出格式

见题面

样例输入
K = 4 str = "1234567"
样例输出
7654321