```
class Solution {
public:
int findPeakElement(vector<int>& nums) {
int left = 0, right = nums.size()-1, mid = 0;
while (left < right)
{
mid = left + (right - left) / 2;
if (nums[mid] > nums[mid+1])
right = mid;
else
left = mid + 1;
}
return left;
}
};
```