four_sum.go

package four_sum

import (
"sort"
)

funcfourSum(nums []int, targetint) [][]int {
sort.Ints(nums)
varret [][]int
fori:=0; i<len(nums)-3; i++ {
ifi>0&&nums[i-1] ==nums[i] {
continue
 }
forj:=i+1; j<len(nums)-2; j++ {
ifj>i+1&&nums[j-1] ==nums[j] {
continue
 }
left, right:=j+1, len(nums)-1
forleft<right {
ifleft>j+1&&nums[left-1] ==nums[left] {
left++
continue
 }
ifnums[i]+nums[j]+nums[left]+nums[right] ==target {
ret=append(ret, []int{nums[i], nums[j], nums[left], nums[right]})
left++
right--
 } elseifnums[i]+nums[j]+nums[left]+nums[right] <target {
left++
 } else {
right--
 }
 }
 }
 }
returnret
}