English
944. Delete Columns to Make Sorted
Problem Statement
You are given an array of n
strings strs
, all of the same length.
The strings can be arranged such that there is one on each line, making a grid.
- For example,
strs = ["abc", "bce", "cae"]
can be arranged as follows:
abc bce cae
You want to delete the columns that are not sorted lexicographically. In the above example (0-indexed), columns 0 ('a'
, 'b'
, 'c'
) and 2 ('c'
, 'e'
, 'e'
) are sorted, while column 1 ('b'
, 'c'
, 'a'
) is not, so you would delete column 1.
Return the number of columns that you will delete.
Example 1:
Input: strs = ["cba","daf","ghi"] Output: 1 Explanation: The grid looks as follows: cba daf ghi Columns 0 and 2 are sorted, but column 1 is not, so you only need to delete 1 column.
Example 2:
Input: strs = ["a","b"] Output: 0 Explanation: The grid looks as follows: a b Column 0 is the only column and is sorted, so you will not delete any columns.
Example 3:
Input: strs = ["zyx","wvu","tsr"] Output: 3 Explanation: The grid looks as follows: zyx wvu tsr All 3 columns are not sorted, so you will delete all 3.
Constraints:
n == strs.length
1 <= n <= 100
1 <= strs[i].length <= 1000
strs[i]
consists of lowercase English letters.
Solution:
java
class Solution {
public int minDeletionSize(String[] strs) {
if (strs == null || strs.length == 0)
return 0;
int count = 0;
for (int i = 0; i < strs[0].length(); i++) {
char ch = strs[0].charAt(i);
for (int j = 0; j < strs.length; j++) {
char curr = strs[j].charAt(i);
if (curr < ch) {
count++;
break;
}
ch = curr;
}
}
return count;
}
}
...