算法训练营day72

题目：117. 软件构建 (kamacoder.com)

#include<iostream>
#include<unordered_map>
#include<vector>
#include<queue>

using namespace std;

int main() {
    int n, m;
    cin >> n >> m;
    vector<int> indegree(n, 0);
    unordered_map<int, vector<int>> map;
    int s, t;
    while(m--) {
        cin >> s >> t;
        indegree[t]++;
        map[s].push_back(t);
    }
    queue<int> qu;
    for(int i = 0;i < n;i++) {
        if(indegree[i] == 0) {
            qu.push(i);
        }
    }
    vector<int> result;
    while(!qu.empty()) {
        int cur = qu.front();
        qu.pop();
        result.push_back(cur);
        vector<int> files = map[cur];
        if(files.size()) {
            for(int i = 0;i < files.size();i++) {
                indegree[files[i]]--;
                if(indegree[files[i]] == 0) qu.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;
    }
    return 0;
}

题目2：47. 参加科学大会（第六期模拟笔试） (kamacoder.com)

#include<bits/stdc++.h>

using namespace std;

int main() {
    int n, m;
    cin >> n >> m;
    vector<vector<int>> grid(n + 1, vector<int>(n + 1, INT_MAX));
    vector<bool> vistied(n + 1, false);
    vector<int> minDist(n + 1, INT_MAX);
    while(m--) {
        int s, e, v;
        cin >> s >> e >> v;
        grid[s][e] = v;
    }
    minDist[1] = 0;
    int cur = 1;

    for(int i = 1;i <= n;i++) {
        int minVal = INT_MAX;
        for(int v = 1;v <= n;v++) {
            if(!vistied[v] && minDist[v] < minVal) {
                minVal = minDist[v];
                cur = v;
            }
        }
        vistied[cur] = true;
        for(int j = 1;j <= n;j++) {
            if(!vistied[j] && grid[cur][j] != INT_MAX && minDist[cur] + grid[cur][j] < minDist[j]) {
                minDist[j] = minDist[cur] + grid[cur][j];
            }
        }
    }
    if(minDist[n] == INT_MAX) cout << -1 << endl;
    else cout << minDist[n] << endl;
    return 0;
}