public static string gridChallenge(List<string> grid)
    {
        char[] letters;
        
        for (int i = 0; i < grid.Count(); i++){
            letters = grid[i].ToCharArray();
            
            Array.Sort(letters);
            grid[i] = new string(letters);
        }
        
        for (int i = 0; i < grid[0].Length; i++){
            letters = new char[grid.Count()];
            
            for(int j = 0; j < grid.Count(); j++){
                letters[j] = grid[j][i];
            }
            
            string preSort = new string(letters);
            Array.Sort(letters);
            if (new string(letters) != preSort){
                return "NO";
            }
        }
        
        return "YES";
    }

function gridChallenge(grid: string[]): string {
    const sortedGrid = grid.map(row => [...row].sort().join(""));
    
    for(let i = 0; i < sortedGrid[0].length; i++) {
        let lastAsciiCode = 'a'.charCodeAt(0);
        for(let j = 0; j < sortedGrid.length; j++) {
            const charCode = sortedGrid[j].charCodeAt(i);
            if (charCode < lastAsciiCode) {
                return "NO";
            } 
            lastAsciiCode = charCode;
        }
    }
        
    return "YES";
}

public static String gridChallenge(List<String> grid) {
        for (int i=0; i<grid.size(); i++) {
            char[] charArr = grid.get(i).toCharArray();
            Arrays.sort(charArr);
            String str = new String(charArr);
            grid.set(i, str);
        }
        for (int i=0; i<grid.get(0).length(); i++) {
            int charVal = 'a';
            for (String string : grid) {            
                if (string.charAt(i) < charVal) return "NO";
                charVal = string.charAt(i);
            }
        }  
        return "YES";

    }

def gridChallenge(grid):
    
    for i in range(len(grid)):
        grid[i] = sorted(grid[i])
        
    for i in range(len(grid[0])):
        for j in range(len(grid) - 1):
            if grid[j][i] > grid[j + 1][i]:
                return "NO"
                
    return "YES"