我正在努力进行 minimax 练习，我只是想用它连接四个 ai。我的仅在深入探索一个节点时有效，但我无法弄清楚为什么一旦深入就会搞砸。
private int minimax(Gameboard gameBoard, int alpha, int depth, char color) {
Gameboard gb = new Gameboard(gameBoard);
int value = 0;
int bestChoice = 0;
int bestValue = alpha;
// determine which use the value is for
if (gb.computerColor == color) {
value = 1;
} else {
value = -1;
}
if (gb.CheckForWinner(gb.lastSpacePlayed)) {
if(gb.winner == gb.computerColor){
bestValue = (1000000000 - depth);
}else{
bestValue = (-1000000000 - depth);
}
}
// get the bestValue at our maximum recrusion depth
else if (depth == maxDepth) {
int moveWeight = (threatLevel(gb, color));
if (moveWeight != 0) {
bestValue = value * (moveWeight - depth);
} else {
bestValue = moveWeight;
}
} else {
// Generate moves for each col and find the best score from each of
// the generated moves.
for (int c = 0; c < 7; c++) {
Gameboard game = new Gameboard(gb);
int selectedPlace = game.PlacePiece(c, color);
// Recursive call the generated game grid and compare the
// current value to move value
// If move is higher, make it the new current value.
if (selectedPlace != -1) {
char tempColor;
// change the user for the child node after a piece is played
if (color == 'Y') {
tempColor = 'R';
} else {
tempColor = 'Y';
}
// call the function so we can explore to maximum depth
if (depth < maxDepth) {
int v = minimax(new Gameboard(game), -1000000, depth + 1, tempColor);
if (v > bestValue) {
bestChoice = c;
bestValue = v;
}
System.out.println(v);
}
}
}
}
if (depth == 0) {
if (threatLevel(gb, gb.lastSpacePlayed.getColor()) == 0) {
return gb.spaces.get(0).get(3).getColor() == gb.playerColor ? 2
: 3;
} else {
return bestChoice;
}
} else {
return bestValue;
}
}
我是这样开始的 return minimax(gameBoard, -1000000, 0, gameBoard.computerColor);
我的理解是遍历所有子节点并返回一个值，如果节点与父节点相同，则返回最大值，如果节点不同，则返回最小值。任何方向将不胜感激。
最佳答案
private int minimax(Gameboard gameBoard, int depth, char color) {
Gameboard gb = new Gameboard(gameBoard);
int bestChoice = 0;
int bestValue = 0;
//If we've won, return highest possible value. If we've lost, return lowest.
if (gb.CheckForWinner(gb.lastSpacePlayed)) {
if(gb.winner == color){
return Integer.MAX_VALUE
}else{
return Integer.MIN_VALUE
}
}
//if we hit maximum depth, resort to our heuristic method.
else if (depth == maxDepth) {
return threatLevel(gb, color);
} else {
// Generate moves for each col and find the best score from each of
// the generated moves. Keep track of the worst one.
int worstBestResponse = Integer.MAX_INT
boolean tie = true;
for (int c = 0; c < 7; c++) {
Gameboard game = new Gameboard(gb);
int selectedPlace = game.PlacePiece(c, color);
// Recursive call the generated game grid and compare the
// current value to move value
// If move is higher, make it the new current value.
if (selectedPlace != -1) {
tie = false;
char tempColor;
// change the user for the child node after a piece is played
if (color == 'Y') {
tempColor = 'R';
} else {
tempColor = 'Y';
}
// call the function so we can explore to maximum depth
if (depth < maxDepth) {
int v = minimax(new Gameboard(game), depth + 1, tempColor);
if (v < worstBestResponse) {
worstBestResponse = v;
}
}
}
}
if(tie) {
//if game is a tie, we return 0, to show no favour.
return 0;
} else {
//After determining the value of the opponents best response, we return the negative value of it. That is, what's bad for them is good for us and visa versa.
return -worstBestResponse;
}
}
}
我相信这样的东西更符合您的需求。这是假设 threatLevel 是一种启发式方法，用于大致确定谁在给定游戏中获胜。
我已经删除了该方法可能拥有的关于它支持谁的任何信息。它应该只支持“颜色”是谁。我还清理了任意大的整数以显示输赢。 MAX_VALUE 和 MIN_VALUE 更优雅。
无论如何，试试这个，并用深度为 0 调用它。如果您有任何问题，请告诉我
关于java - 极小极大问题——连接四个。，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/39007906/