CareerCup

Can you explain what your'e doing?

Good & simple.

I like this solution. Very simple and O(n) time and O(1) space.

Good & simple.

public class MaxLengthPalindrome {
	public static int[] a= {4,12,3,4,5,6,4,3,4,4,4,4,4,4,4};
	public static int maxLength(int i, int j) {
		if (Math.abs(i-j)==1 || Math.abs(i-j)==0) return a[i]==a[j]?2:1;
		System.out.println(i + " " + j);
		if (a[i]==a[j])
			return 2+maxLength(i+1,j-1);
		return Math.max(maxLength(i+1,j), maxLength(i,j-1));
	}
	public static void main(String[] args) {
		System.out.println(maxLength(0,a.length-1));
	}

}

public class MaxLengthPalindrome {
	public static int[] a= {4,12,3,4,5,6,4,3,4,4,4,4,4,4,4};
	public static int maxLength(int i, int j) {
		if (Math.abs(i-j)==1 || Math.abs(i-j)==0) return a[i]==a[j]?2:1;
		System.out.println(i + " " + j);
		if (a[i]==a[j])
			return 2+maxLength(i+1,j-1);
		return Math.max(maxLength(i+1,j), maxLength(i,j-1));
	}
	public static void main(String[] args) {
		System.out.println(maxLength(0,a.length-1));
	}

}

import java.util.Arrays;

public class TriangleTriplets {

        //note: you don't need to check the other two cases since the array is sorted. 
	public static boolean check(int a, int b, int c) {
		return (a+b>c);
	}
	
	public static void triangleTriples(int[] a) {
		for (int i = 0; i<a.length; i++) {
			for (int j = i+1; j<a.length; j++) {
				for (int k = j+1; k<a.length; k++) {
					if (check(a[i],a[j],a[k])) 
						System.out.println(a[i] + " " + a[j] + " " + a[k]);
				}
			}
		}		
	}

	public static void main(String[] args) {
		int[] a = {7,8,9,10};
		Arrays.sort(a);
		triangleTriples(a);
	}
}

What is k initialized as? And don't you need to make sure a[k] is not the same as a[i] or a[j]?

Can you be more specific?