Leetcode 514. Freedom Trail
阿新 • • 發佈:2019-02-01
In the video game Fallout 4, the quest “Road to Freedom” requires players to reach a metal dial called the “Freedom Trail Ring”, and use the dial to spell a specific keyword in order to open the door.
Given a string ring, which represents the code engraved on the outer ring and another string key
At the stage of rotating the ring to spell the key character key[i]:
- You can rotate the ring clockwise or anticlockwise one place, which counts as 1 step. The final purpose of the rotation is to align one of the string ring’s characters at the 12:00 direction, where this character must equal to the character key[i]
- If the character key[i] has been aligned at the 12:00 direction, you need to press the center button to spell, which also counts as 1 step. After the pressing, you could begin to spell the next character in the key (next stage), otherwise, you’ve finished all the spelling.
Example:
Input: ring = “godding”, key = “gd” Output: 4 Explanation:
For the first key character ‘g’, since it is already in place, we just need 1 step to spell this character.
For the second key character ‘d’, we need to rotate the ring “godding” anticlockwise by two steps to make it become “ddinggo”.
Also, we need 1 more step for spelling.
So the final output is 4.
Note:
- Length of both ring and key will be in range 1 to 100.
- There are only lowercase letters in both strings and might be some duplcate characters in both strings.
- It’s guaranteed that string key could always be spelled by rotating the string ring.