Delete Columns to Make Sorted

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:

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:

Language: Java

class Solution 
{
    public int minDeletionSize(String[] strs) 
    {
        int len = strs.length ;
        int wordlen = strs[0].length() ;
        int count=0 ;

        for(int i=0;i<wordlen;i++)
        {
            char prev= strs[0].charAt(i) ;
            for(int j=1;j<len;j++)
            {
                char ch = strs[j].charAt(i) ;
                if(ch<prev)
                {
                    count++ ;
                    break ;
                }
                prev = ch ;
            }
        }
               return count ;

    }
}