題目
Given a sorted array, remove the duplicates in place such that each element appear only once and return the new length.
Do not allocate extra space for another array, you must do this in place with constant memory.
For example,
Given input array nums = [1,1,2],
Your function should return length = 2, with the first two elements of nums being 1 and 2 respectively. It doesn't matter what you leave beyond the new length.
解題思路
對于一個排好序的數(shù)組來說，A[N + 1] >= A[N]，使用兩個游標i和j來處理，假設現(xiàn)在i = j + 1，如果A[i] == A[j]，那么我們遞增i，直到A[i] > A[j]，這時候找到了更大的值，此時遞增j，再設置A[j] = A[i]，然后遞增i，重復上述過程直到遍歷結束。
代碼
removeDuplicates.go
package _26_Remove_Duplicates_from_Sorted_Array
import "fmt"
func RemoveDuplicates(nums []int) int {
len1 := len(nums)
if 0 == len1 {
return 0
}
i, j := 1, 0
for ; i < len1; i++{
if nums[i] > nums[j]{
j++
nums[j] = nums[i]
}
}
j++
fmt.Printf("nums:%+v\n", nums)
return j
}
測試
removeDuplicates_test.go
package _26_Remove_Duplicates_from_Sorted_Array
import "testing"
func TestRemoveDuplicates(t *testing.T) {
var tests = []struct{
input []int
ret int
} {
{[]int{1, 1}, 1},
{[]int{1,1,1}, 1},
{[]int{1,2,2,3}, 3},
{[]int{-999,-999,-998,-998,-997,-997}, 3},
}
for _, v := range tests {
ret := RemoveDuplicates(v.input)
if ret == v.ret {
t.Logf("pass")
} else {
t.Errorf("fail, want %+v, get %+v", v.ret, ret)
}
}
}
