27. Remove Element
题目
Given an array and a value, remove all instances of that value in-place and return the new length.
Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.
The order of elements can be changed. It doesn't matter what you leave beyond the new length.
Example:
Given nums = [3,2,2,3], val = 3,
Your function should return length = 2, with the first two elements of nums being 2.
解析
class Solution_27 {
public:
// 直接查看cnt长度的元素值；若是str,最后加上‘\0’
int removeElement(vector<int>& nums, int val) {
int cnt = 0;
for (int i = 0; i < nums.size();i++)
{
if (nums[i]!=val)
{
nums[cnt++] = nums[i];
}
}
return cnt;
}
//测试用例: 牛客网上有顺序要求
// [1, 2, 3, 4], 1
//
// 对应输出应该为 :
//
// [4, 2, 3]
//
//你的输出为 :
//
// [2, 3, 4]
int removeElement(int A[], int n, int elem) {
int i = 0;
for ( i= 0; i < n; i++)
{
if (A[i] == elem)
{
while (i<n&&A[--n] == elem);
A[i] = A[n];
}
}
return n;
}
};
题目来源
