Hello guys,

This is my code, should be the same as most of the codes I see in the forum, I wonder why I got runtime error for input of {1} on judge, when I run it locally,it works fine for me, thank you.

```
class Solution {
public:
int firstMissingPositive(vector<int>& nums) {
int i =0;
int n = nums.size();
while(i < n) {
if(nums[i] <= 0 || nums[i] > n ||
nums[i] == nums[nums[i]-1]) i++;
swap(nums[i], nums[nums[i]-1]);
}
for(int i=0; i < n; ++i){
if(nums[i] != i+1) return i+1;
}
return n+1;
}
};
```