n·log n 大约多少次
运行下面这段程序,它粗略数了 n = 100000 时 n·log n 的次数:
#include <iostream>
#include <string>
#include <vector>
using namespace std;
int main() {
long long n = 100000, ops = 0;
for (long long i = 1; i <= n; i *= 2) ops += n;
cout << ops << endl;
}
(本题用 g++ -std=c++17 -O0 编译。)