题目地址:
https://leetcode.com/problems/valid-word-square/
给定一个字符串列表,判断一下其作为字符二维矩阵是否关于从左上到右下的对角线对称。可以将每列的字符串求出来,然后和对应行的字符串进行比较。代码如下:
class Solution {
public boolean validWordSquare(List<String> words) {
if (words == null || words.isEmpty()) {
return true;
}
StringBuilder sb = new StringBuilder();
int n = words.get(0).length();
for (int i = 0; i < n; i++) {
sb.setLength(0);
for (int j = 0; j < words.size(); j++) {
if (i < words.get(j).length()) {
sb.append(words.get(j).charAt(i));
} else {
break;
}
}
if (!sb.toString().equals(words.get(i))) {
return false;
}
}
return true;
}
}
时间复杂度,空间复杂度,为行数,为列数。