Given an array of n integers where n > 1, nums
,
return an array output
such that output[i]
is
equal to the product of all the elements of nums
except nums[i]
.
Solve it without division and in O(n).
For example, given [1,2,3,4]
, return [24,12,8,6]
.
Follow up:
Could you solve it with constant space complexity? (Note: The output array does not count as extra space for the purpose of space complexity analysis.)
实现:
class Solution {
public:
vector<int> productExceptSelf(vector<int>& nums) {
vector<int> result;
int curr = 1;
for (int i = 0; i < nums.size(); ++i) {
result.push_back(curr);
curr = curr * nums[i];
}
curr = 1;
for (int i = nums.size() - 1; i >= 0; --i)
{
result[i] = result[i] * curr;
curr = curr * nums[i];
}
return result;
}
};