class Solution {
    public int minDeletionSize(String[] strs) {
        int count=0;
        for(int i=0; i<strs[0].length(); i++){
            for(int j=0; j<strs.length-1; j++){
                if(strs[j].charAt(i)>strs[j+1].charAt(i)){
                    count++;
                    break;
                }
            }
        }
        
        return count;
    }
}