最近开始学习运筹学方面的内容……

首先是学习了线性规划

某公司生产甲、乙两种产品，均需在A、B、C三种不同的设备上加工，产品加工所需工时单耗、产品销售后能获得的利润及设备可用工时数如下表所示。问：如何安排生产计划，才能使该公司获得的总利润最大？


用枚举法做这道题：

#include <stdio.h>
#include <windows.h>

class CTimer
{
public:
    __forceinline CTimer( void ) {
        QueryPerformanceFrequency( (PLARGE_INTEGER)&m_nFreq );
        QueryPerformanceCounter( (PLARGE_INTEGER)&m_nStart ); }
    __forceinline void Reset( void ) {
        QueryPerformanceCounter( (PLARGE_INTEGER)&m_nStart ); }
    __forceinline double Stop( void ) {
        QueryPerformanceCounter( (PLARGE_INTEGER)&m_nCur );
        return double( m_nCur - m_nStart ) / double( m_nFreq ); }
    __forceinline bool SelfTest( void ){
        return ( 0 != QueryPerformanceFrequency( (PLARGE_INTEGER)&m_nFreq ) ); }
private:
    __int64 m_nCur;
    __int64 m_nFreq;
    __int64 m_nStart;
};

int main(){
    int i,j;
    int a,b,x,y;
    CTimer tmr;
    b=-1;
    for(i=0;;i++){
        if((3*i>540)&&(5*i>450)&&(9*i>720)) break;
        for(j=0;(3*i+9*j<=540)&&(5*i+5*j<=450)&&(9*i+3*j<=720);j++){
            a=70*i+30*j;
            if(b==-1||a>b){
                b=a;x=i;y=j;
            }
        }
    }

    printf("x=%d, y=%d ==> %d\nuse time: %f ms\n",x,y,b,tmr.Stop()*1000);
    return 0;
}


运行结果为：

x=75, y=15 ==> 5700
use time: 0.107556 ms
Press any key to continue

只用了0.1毫秒就解决了问题……