Crashing Robots
题意
- 模拟多个机器人在四个方向的移动,检测crash robot, crash wall, OK这些状态
- 这是个模拟题需要注意几点:
- 理解转变方向后移动多少米,和转动方向多少次的区别,这里后一种,在于自己审题
- crash robot 需要
区别哪一个是最先找到的
代码(自己写的比较乱)
int move[4][2]={{1,0},{0,1},{-1,0},{0,-1}};
//1..A or B
std::map<char,int> mp={{'E',0},{'N',1},{'W',2},{'S',3}};
struct node{
int x,y;
int dir;
};//record position
int xb,yb;//x,y边界
node pos[105];//记录当前robot 位置
int ros,ins;//robots num and instruction nums
bool cr(int x1,int x2,int x){
return (x1<=x&&x<=x2)||(x2<=x&&x<=x1);
}
bool crash_robot(node b,node e,node r){
if(cr(b.x,e.x,r.x)&&cr(b.y,e.y,r.y)) return true;
else return false;
}
int check(int a, char ins,int len){
//return 1 crash robot 2 crash wall 3 OK temparily
//
node tmp=pos[a];
if(ins=='L'){
pos[a].dir=(pos[a].dir+len)%4;
}
else if(ins=='R'){
pos[a].dir=(pos[a].dir-len+400)%4;
}
//
else if(ins=='F'){
tmp.x=pos[a].x+move[pos[a].dir][0]*len;
tmp.y=pos[a].y+move[pos[a].dir][1]*len;
tmp.dir=pos[a].dir;
int near_rob=-1;
for(int j=1;j<=ros;j++){
//需要判断谁先撞上
if(j!=a){
if(crash_robot(pos[a],tmp,pos[j])){
if(near_rob==-1) near_rob=j;
else {
if(abs(pos[j].x-pos[a].x+pos[j].y-pos[a].y)<abs(pos[near_rob].x+pos[near_rob].y-pos[a].x-pos[a].y)) near_rob=j;
}
//printf("Robot %d crashes into robot %d
",a,j);
}
}
}
pos[a]=tmp;
if(near_rob!=-1){
printf("Robot %d crashes into robot %d
",a,near_rob);
return 1;
}
//no crash robot
//check crash wall
if(tmp.x<=0||tmp.x>=xb+1||tmp.y<=0||tmp.y>=yb+1){
printf("Robot %d crashes into the wall
",a);
pos[a]=tmp;
return 2;
}
pos[a]=tmp;
}
return 0;
}