The numeric value of a lowercase character is defined as its position (1-indexed) in the alphabet, so the numeric value of a is 1, the numeric value of b is 2, the numeric value of c is 3, and so on.
The numeric value of a string consisting of lowercase characters is defined as the sum of its characters’ numeric values. For example, the numeric value of the string "abe" is equal to 1 + 2 + 5 = 8.
You are given two integers n and k. Return the lexicographically smallest string with length equal to n and numeric value equal to k.
Note that a string x is lexicographically smaller than string y if x comes before y in dictionary order, that is, either x is a prefix of y, or if i is the first position such that x[i] != y[i], then x[i] comes before y[i] in alphabetic order.
Example 1:
Input: n = 3, k = 27 Output: "aay" Explanation: The numeric value of the string is 1 + 1 + 25 = 27, and it is the smallest string with such a value and length equal to 3.
Example 2:
Input: n = 5, k = 73 Output: "aaszz"
Constraints:
1 <= n <= 105n <= k <= 26 * n
Solution: Greedy, Fill in reverse order
Fill the entire string with ‘a’, k-=n, then fill in reverse order, replace ‘a’ with ‘z’ until not enough k left.
Time complexity: O(n)
Space complexity: O(n)
C++
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
// Author: Huahua class Solution { public: string getSmallestString(int n, int k) { string ans(n, 'a'); k -= n; while (k) { int d = min(k, 25); ans[--n] += d; k -= d; } return ans; } }; |
Python3
|
1 2 3 4 5 6 7 8 9 10 11 12 |
# Author: Huahua class Solution: def getSmallestString(self, n: int, k: int) -> str: ans = ['a'] * n k -= n i = n - 1 while k: d = min(k, 25) ans[i] = chr(ord(ans[i]) + d) k -= d i -= 1 return ''.join(ans) |
请尊重作者的劳动成果，转载请注明出处！花花保留对文章／视频的所有权利。
如果您喜欢这篇文章／视频，欢迎您捐赠花花。
If you like my articles / videos, donations are welcome.
huahualeetcode
Be First to Comment