TSP问题

思路

用一个visited数组保存每个城市被访问的情况，0代表未被访问，1代表被访问；
用一个distance数组来存储任意两个城市之间的距离；
用minDistance来表示当前遍历出的最小距离，对应城市为minDistanceCity；
用cityVistited存储已经经过的城市数；
用currentCity表示当前所在的城市。

代码实现

public int TSP(int[][] distance) {
	// 1 represent the city has been visited
	// 0 represent the city hasn't been visited
	int[] visited = new int[distance.length];
	int sum = 0;
	// current position is the city 0
	int currentCity = 0;
	int cityVisited = 1;
	visited[currentCity] = 1;
	// make sure there are at least two cities
	while (cityVisited < distance.length) {
		// initialized minDistance
		int minDistance = Integer.MAX_VALUE;
		int minDistanceCity = Integer.MAX_VALUE;
		for (int j=0; j < visited.length; j++) {
			if (visited[j] == 0 && distance[currentCity][j] < minDistance && j != currentCity) {
				minDistance = distance[currentCity][j];
				minDistanceCity = j;
			}
		}
		currentCity = minDistanceCity;
		sum += minDistance;
		cityVisited++;
		visited[currentCity] = 1;
		System.out.println(" " + currentCity);
	}
	System.out.println();
	return sum;
}