【数据结构】图的邻接表构建（代码实现）

#include <iostream>
#include <map>
#include <vector>
#include <string>
using namespace std;

构建函数

void build_Adj_List(vector<vector<pair<int, int>>> &adjList, vector<string> &node, int num, int edges) {


	// adjList邻接表，node节点名称，num节点个数，edges边的个数


	// 存储节点名字
	for (int i = 0; i < num; i++) {
		cin >> node[i];
	}

	// 存储边
	for (int i = 0; i < edges; i++) {

		string start, end;
		int weight;

		cin >> start >> end >> weight;

		int from = -1;
		int to = -1;
		for (int j = 0; j < num; j++) {
			if (start == node[j]) from = j;
			if (end == node[j]) to = j;
		}

		if (from != -1 and to != -1) {

			// 存储指向的节点下标以及路径权重
			pair<int, int> p(to, weight);

			// 向from节点下标的数组中插入键值对，键为to节点下标，值为路径权重
			adjList[from].push_back(p);
		}

	}

}

打印函数

void print_Adj_List(vector<vector<pair<int, int>>> & adjList, vector<string> &node) {


	for (int i = 0; i < node.size(); i++) {

		if (!adjList[i].empty()) {
			cout << "from " << node[i] << " ";

			for (int j = 0; j < adjList[i].size(); j++) {

				if (j != 0) {
					cout << "from " << node[i] << " ";
				}
				cout << "to " << node[adjList[i][j].first] << " "
					<< "weight " << adjList[i][j].second << endl;
			}
		}

	}


}

主函数

int main_adj_list() {

	int num;
	cin >> num;

	vector<string> node(num);
	vector<vector<pair<int, int>>> adjList(num);

	int edges;
	cin >> edges;

	

	build_Adj_List(adjList, node, num, edges);

	print_Adj_List(adjList, node);




	return 0;
}