算法训练营|图论第8天 拓扑排序 dijkstra
题目：
拓扑排序
题目链接：
117. 软件构建 (kamacoder.com)
代码：
#include<bits/stdc++.h>
#include<unordered_map>
using namespace std;
int main() {int n, m;cin >> n >> m;vector<int>inDegree(n, 0);unordered_map<int, vector<int>>myMap;vector<int>result;for (int i = 0; i < m; i++) {int s, t;cin >> s >> t;inDegree[t]++;myMap[s].push_back(t);}queue<int>que;for (int i = 0; i < n; i++) {if (inDegree[i] == 0) {que.push(i);}}while (!que.empty()) {int cur = que.front();que.pop();result.push_back(cur);vector<int>files = myMap[cur];if (files.size() != 0) {for (int i = 0; i < files.size(); i++) {inDegree[files[i]]--;if (inDegree[files[i]] == 0) {que.push(files[i]);}}}}if (result.size() == n) {for (int i = 0; i < n - 1; i++) {cout << result[i] << ' ';}cout << result[n - 1] << endl;}else {cout << -1 << endl;}
}题目：
dijkstra
题目链接：
47. 参加科学大会（第六期模拟笔试） (kamacoder.com)
代码：
#include<bits/stdc++.h>
using namespace std;
int main() {int n, m, s, e, v;cin >> n >> m;vector<vector<int>>grid(n + 1, vector<int>(n + 1, INT_MAX));for (int i = 0; i < m; i++) {cin >> s >> e >> v;grid[s][e] = v;}vector<int>minDist(n + 1, INT_MAX);vector<bool>visited(n + 1, false);int start = 1;int end = n;minDist[start] = 0;for (int i = 1; i <= n; i++) {int minVal = INT_MAX;int cur = 1;for (int v = 1; v <= n; v++) {if (!visited[v] && minDist[v] < minVal) {cur = v;minVal = minDist[v];}visited[cur] = true;for (int v = 1; v <= n; v++) {if (!visited[v] && grid[cur][v] != INT_MAX && minDist[cur] + grid[cur][v] < minDist[v]) {minDist[v] = minDist[cur] + grid[cur][v];}}}}if (minDist[end] == INT_MAX) cout << -1 << endl;else {cout << minDist[end] << endl;}
}