/**

* res.js

* @authors Joe Jiang ([email protected])

* @date 2017-04-03 23:45:47

*

* @param {number[]} nums

* @return {number[][]}

*/

let threeSum = function(nums) {

nums.sort(function(a, b) {

return a - b;

});

let numlen = nums.length,

end = nums[numlen - 1],

eInd = numlen - 2,

res = [];

if (numlen < 3 || nums[0] > 0 || end < 0) {

return [];

}

for (let i = 0; i < eInd; i++) {

let revi = -nums[i],

j = i + 1,

k = numlen - 1;

if (revi < 0) {

break;

}

while (j < k) {

let norj = nums[j],

nork = nums[k];

if (norj + nork > revi) {

k--;

} else if (norj + nork < revi) {

j++;

} else {

res.push([nums[i], nums[j], nums[k]]);

// forbid duplicated numbers

while (j + 1 < numlen && nums[j] === nums[j + 1]) j++;

while (nums[k] === nums[k - 1]) k--;

k--;

j++;

}

}

while (i + 1 < numlen && nums[i] === nums[i + 1]) i++;

}

return res;

};