有个内含单词的超大文本文件,给定任意两个不同的单词,找出在这个文件中这两个单词的最短距离(相隔单词数)。如果寻找过程在这个文件中会重复多次,而每次寻找的单词不同,你能对此优化吗?
输入:words = ["I","am","a","student","from","a","university","in","a","city"], word1 = "a", word2 = "student"
输出:1
words.length <= 100000
双指针,遍历字符串数组,不断维护两个指针即可。
class Solution { public int findClosest(String[] words, String word1, String word2) { int index1 = -1; int index2 = -1; int ans = 100001; for(int i=0; i<words.length; i++) { String word = words[i]; if( word.equals(word1) ) { index1 = i; } if( word.equals(word2) ) { index2 = i; } if( index1!=-1 && index2!=-1 ) { ans = Math.min(ans, Math.abs(index2-index1)); } } return ans; } }