my @tests = (
    [[2,7,11,15], 9, [0,1]],
    [[2,7,11,15], 9, [1,0]],
    [[3,2,4], 6, [1,2]],
    [[3,2,4], 6, [2,1]],
    [[3,3], 6, [0,1]],
    [[3,3], 6, [1,0]],
);