2009/10/29

[ C/C++ ] Powers Of Two by C++

使用 C++ 輸出 2 的次方值 Power Of Two

// powersOfTwo.cpp
//
// Powers of Two, 2^i 
//
// Console-based
// Author Jim.lin 2009

#include <iostream>

using namespace std;

int main()
{
    int N;
    int v = 1;
    int i = 0;
    cin >> N;
    while(i <= N)
    {
        cout << i << " " << v << endl;
        v = 2 * v;
        i = i + 1;
    }
}

2 意見:

subineru 提到...

直接 shift bit 會不會比較快呢?
000000010 2
000000100 4
以下略...

4wei-diary 提到...

嗯 ~ left shift 的確比較省 ~~

int main()
{
int N;
int x = 2;
int y;
cin >> N;
y = x << N-1;
cout << " Result : " << y << endl;
}