41 lines
1.2 KiB
TypeScript
41 lines
1.2 KiB
TypeScript
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/**
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* 计算路径给定的IUnweightedGraph和开始/目标位置
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*/
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class BreadthFirstPathfinder {
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public static search<T>(graph: IUnweightedGraph<T>, start: T, goal: T): T[]{
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let foundPath = false;
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let frontier = [];
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frontier.unshift(start);
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let cameFrom = new Map<T, T>();
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cameFrom.set(start, start);
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while (frontier.length > 0){
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let current = frontier.shift();
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if (JSON.stringify(current) == JSON.stringify(goal)){
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foundPath = true;
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break;
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}
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graph.getNeighbors(current).forEach(next => {
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if (!this.hasKey(cameFrom, next)){
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frontier.unshift(next);
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cameFrom.set(next, current);
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}
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});
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}
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return foundPath ? AStarPathfinder.recontructPath(cameFrom, start, goal) : null;
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}
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private static hasKey<T>(map: Map<T, T>, compareKey: T){
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let iterator = map.keys();
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let r: IteratorResult<T>;
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while (r = iterator.next() , !r.done) {
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if (JSON.stringify(r.value) == JSON.stringify(compareKey))
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return true;
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}
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return false;
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}
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}
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