C/C++取整函数ceil（向上取整）和floor（向下取整）

#include<bits/stdc++.h>
using namespace std;

int main()
{
    
    
    cout<<"1.2向上取整："<<ceil(1.2)<<endl;
    cout<<"0.0向上取整："<<ceil(0.0)<<endl;
    cout<<"-1.2向上取整："<<ceil(-1.2)<<endl;
    cout<<"1.2向下取整："<<floor(1.2)<<endl;
    cout<<"0.0向下取整："<<floor(0.0)<<endl;
    cout<<"-1.2向下取整："<<floor(-1.2)<<endl;
    return 0;
}