W3School TIY Editor

#include <iostream> #include <vector> #include <algorithm> using namespace std; int main() { vector<int> numbers = {1, 7, 3, 5, 9, 2}; auto it = is_sorted_until(numbers.begin(), numbers.end()); int position = it - numbers.begin(); cout << "前 " << position << " 个元素是按升序排列的。"; return 0; }