public class Es5 {

    public static void raddoppia2(int[] l, int[][] m) {
        if (l.length < m.length)
            return;
        for (int i = 0; i < m.length; i++) {
            if (l[i] >= m[i].length)
                return;
        }
        for (int i = 0; i < m.length; i++) {
            m[i][l[i]] *= 2;
        }
    }

}