我正在制作一艘类似Battleship的游戏,需要随机将战列舰物体放入战地图阵列中。除非我这样做,否则船舶不会放在右下象限中(但它们已成功放置在其他三个象限中),我不知道为什么。基本上,我得到一个从0到地图长度和高度以及随机方向的随机整数,然后检查船是否适合,如果可以的话,将它放在地图上。但它绝不会将它们放在右下角。C++:在2D数组中随机放置一个数组
void BattleMap::placeRandomly(BattleShip& ship) {
bool correct = true;
int x_start,y_start,dir;
// size_x, size_y denote the length and height of the array respectively
int length = ship.getLength();
do{
correct = true;
x_start = abs(rand()%(size_x-length));
if(x_start+length > size_x) x_start -= length;
y_start = abs(rand()%(size_y-length));
if(y_start+length > size_y) y_start -= length;
dir = rand()%2; // 0 for vertical, 1 for horizontal;
for (int i = 0; i < length;i++) {
switch(dir){ // Check if there is already a ship in the candidate squares
case 0:
if(this->at(x_start,y_start+i)){
correct = false;
}
break;
case 1:
if(this->at(x_start+i,y_start)){
correct = false;
}
break;
}
}
}while(!correct);
// Place the ships into the array
....
}
的at()
功能是这样的:
BattleShip*& BattleMap::at(int x, int y){
if(x > size_x || y > size_y)return 0;
// error: invalid initialization of non-const reference of type 'BattleShip*&' from a temporary of type 'int'
return board[x*size_y +y];
}
为什么downvote? –