算法—蚂蚁过桥

有一根27厘米的细木杆，在第3厘米、7厘米、11厘米、17厘米、23厘米这五个位置上各有一只蚂蚁。

木杆很细，不能同时通过一只蚂蚁。

开始时，蚂蚁的头朝左还是朝右是任意的，它们只会朝前走或调头，但不会后退。

当任意两只蚂蚁碰头时，两只蚂蚁会同时调头朝反方向走。

假设蚂蚁们每秒钟可以走一厘米的距离。

编写程序，求所有蚂蚁都离开木杆的最小时间和最大时间。

#include<iostream>
using namespace std;
class ant
{
public:
bool orient; //0-left;1-right;
short pos; //0-27;
bool onbar; //0-off;1-on;
void meet()//－－－－－－－－－－－－－－－－－－－－相遇反向
{
orient=orient>0?0:1;
}
void move()//－－－－－－－－－－－－－－－－－－－－未到端点，按方向移动，到则标记
{
if(orient==0) pos--;
else pos++;
if(pos==0||pos==27)onbar=0;
}
};
int main()
{
ant a1,a2,a3,a4,a5;
cout<<"orient(0-left;1-right)"<<endl;
for(int i1=0;i1<=1;i1++)
for(int i2=0;i2<=1;i2++)
for(int i3=0;i3<=1;i3++)
for(int i4=0;i4<=1;i4++)
for(int i5=0;i5<=1;i5++)
{//－－－－－－－－－－－－－－－－－－－－初始化五只蚂蚁
a1.orient=i1;a2.orient=i2;a3.orient=i3;a4.orient=i4;a5.orient=i5;//方向确定
a1.pos=3;a2.pos=7;a3.pos=11;a4.pos=17;a5.pos=23;
a1.onbar=1;a2.onbar=1;a3.onbar=1;a4.onbar=1;a5.onbar=1;
cout<<"orient:"<<a1.orient<<a2.orient<<a3.orient<<a4.orient<<a5.orient<<" ";
short time=0;
while(a1.onbar||a2.onbar||a3.onbar||a4.onbar||a5.onbar)
{//－－－－－－－－－－－－－－－－－－－－蚂蚁在杆上，爬一秒，判断相遇
if(a1.onbar) a1.move();//移动
if(a2.onbar) a2.move();
if(a3.onbar) a3.move();
if(a4.onbar) a4.move();
if(a5.onbar) a5.move();
//方向判断
if(a1.pos+1==a2.pos&&a1.onbar&&a2.onbar){a1.meet();a2.meet();}
if(a2.pos+1==a3.pos&&a2.onbar&&a3.onbar){a2.meet();a3.meet();}
if(a3.pos+1==a4.pos&&a3.onbar&&a4.onbar){a3.meet();a4.meet();}
if(a4.pos+1==a5.pos&&a4.onbar&&a5.onbar){a4.meet();a5.meet();}
time++;
}
cout<<"cost time:"<<time<<"s"<<endl;
}
}
结果：
orient(0-left;1-right) orient:00000 cost time:23s orient:00001 cost time:17s orient:00010 cost time:23s orient:00011 cost time:11s orient:00100 cost time:23s orient:00101 cost time:17s orient:00110 cost time:23s orient:00111 cost time:16s orient:01000 cost time:23s orient:01001 cost time:20s orient:01010 cost time:23s orient:01011 cost time:20s orient:01100 cost time:23s orient:01101 cost time:20s orient:01110 cost time:23s orient:01111 cost time:20s orient:10000 cost time:24s orient:10001 cost time:24s orient:10010 cost time:24s orient:10011 cost time:24s orient:10100 cost time:24s orient:10101 cost time:24s orient:10110 cost time:24s orient:10111 cost time:24s orient:11000 cost time:24s orient:11001 cost time:24s orient:11010 cost time:24s orient:11011 cost time:24s orient:11100 cost time:24s orient:11101 cost time:24s orient:11110 cost time:24s orient:11111 cost time:24s。