public static int countingValleys(int steps, string path)
    {
        if((steps < 2 || steps > Math.Pow(10, 6)) && !path.Contains('U') || !path.Contains('D')) throw new Exception("Pasos invaldos");
        
        
        int countVa = 0;
        
        int level = 0;

        for(int i = 0; i<steps; i++){
            
            if(path[i] == 'U') level++;
            if(path[i] == 'D') level--;
            
            if(path[i] == 'U' && level == 0) countVa++;
        }
        
        return countVa;
    }