Triangle.js

/***


A zero-indexed array A consisting of N integers is given. A triplet (P, Q, R) is triangular if 0 ≤ P < Q < R < N and:

        A[P] + A[Q] > A[R],
        A[Q] + A[R] > A[P],
        A[R] + A[P] > A[Q].

For example, consider array A such that:

  A[0] = 10    A[1] = 2    A[2] = 5
  A[3] = 1     A[4] = 8    A[5] = 20

Triplet (0, 2, 4) is triangular.

Write a function:

    function solution(A); 

that, given a zero-indexed array A consisting of N integers, returns 1 if there exists a triangular triplet for this array and returns 0 otherwise. For example, given array A such that:

  A[0] = 10    A[1] = 2    A[2] = 5
  A[3] = 1     A[4] = 8    A[5] = 20

the function should return 1, as explained above. Given array A such that:

  A[0] = 10    A[1] = 50    A[2] = 5
  A[3] = 1

the function should return 0.

Assume that:

        N is an integer within the range [0..1,000,000];
        each element of array A is an integer within the range [−2,147,483,648..2,147,483,647].

Complexity:

        expected worst-case time complexity is O(N*log(N));
        expected worst-case space complexity is O(N), beyond input storage (not counting the storage required for input arguments).

Elements of input arrays can be modified.
100 33 **/

function solution(A) {
    var long = A.length;
    var aux = A.sort(function(a,b){return a-b;});
    if(long<3){
        return 0;
    }

    for(i = 0; i<long-2; i++){
        if(aux[i]+aux[i+1]>aux[i+2])
            return 1;
    }
    return 0;
    
}


/*O(n³)
function solution(A) {
    var long = A.length;
    for(i=0;i<long-2;i++){
        for(j=i+1; j<long-1; j++){
            for(k=j+1; k<long; k++){
                if(A[i]+A[j]>A[k] && A[i]+A[k]>A[j] && A[j]+A[k]>A[i]){
                    return 1;
                }
            }
        }
    }
    return 0;
}
*/