可以做成鬆餅或蛋糕。
287. Find the Duplicate Number
Given an array of integers nums containing n + 1 integers where each integer is in the range [1, n] inclusive.
There is only one repeated number in nums, return this repeated number.
You must solve the problem without modifying the array nums and uses only constant extra space.
Example 1:
1 | Input: nums = [1,3,4,2,2] |
Example 2:
1 | Input: nums = [3,1,3,4,2] |
香水
記得我們學過氣味的語言,那就用它來說一段話吧。
833. Find And Replace in String
You are given a 0-indexed string s that you must perform k replacement operations on. The replacement operations are given as three 0-indexed parallel arrays, indices, sources, and targets, all of length k.
To complete the ith replacement operation:
Check if the substring sources[i] occurs at index indices[i] in the original string s.
If it does not occur, do nothing.
Otherwise if it does occur, replace that substring with targets[i].
For example, if s = “abcd”, indices[i] = 0, sources[i] = “ab”, and targets[i] = “eee”, then the result of this replacement will be “eeecd”.
All replacement operations must occur simultaneously, meaning the replacement operations should not affect the indexing of each other. The testcases will be generated such that the replacements will not overlap.
For example, a testcase with s = “abc”, indices = [0, 1], and sources = [“ab”,”bc”] will not be generated because the “ab” and “bc” replacements overlap.
Return the resulting string after performing all replacement operations on s.
A substring is a contiguous sequence of characters in a string.
Example 1:
1 | Input: s = "abcd", indices = [0, 2], sources = ["a", "cd"], targets = ["eee", "ffff"] |
Example 2:
1 | Input: s = "abcd", indices = [0, 2], sources = ["ab","ec"], targets = ["eee","ffff"] |
189. Rotate Array
Given an array, rotate the array to the right by k steps, where k is non-negative.
Example 1:
1 | Input: nums = [1,2,3,4,5,6,7], k = 3 |
Example 2:
1 | Input: nums = [-1,-100,3,99], k = 2 |