csr2

public class csr2{


    //csr2:given a string S and an Integer n <= the length of S,
    //generate all possible combinations of length n from the given string S.

    static String s ;
    static char[] c ;
    static int v ;

    public static void combinations(String s, int n){
        csr2.s = s ;
        c = new char[n];
        v = 0;
        comb(0,0);
    }

    public static void comb(int n, int start){
        if (n>=c.length){
            System.out.println(c);
        }

        else for (int i = start; i < s.length(); i++) {
            c[n] = s.charAt(i);
            comb(n+1, i+1);
        }
    }

    public static void main(String[] args) {
        combinations("abc",2);
    }

}