最短路算法包

标签： ACM 最短路

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#include<iostream>#include<string>#include<string.h>#include<algorithm>#include<iomanip>#include<cstdio>#include<queue>#include<stack> #include<vector>#include<functional>  #define INF 99999using namespace std;typedef pair<int, int> P;struct edge {    int from, to, cost;};int n, m;           //n为顶点数，m为边数int a[100][100];void warshall(){    int b[100][100] = { 0 };    for (int i = 0; i <= n; i++)        for (int j = 0; j <= n; j++)            b[i][j] = a[i][j];    cout << "Floyd-warshall: \n";    for (int i = 1; i <= n; i++)    {        for (int j = 1; j <= n; j++)        {            for (int k = 1; k <= n; k++)            {                if (b[j][k] > b[j][i] + b[i][k])                {                    b[j][k] = b[j][i] + b[i][k];                }            }        }    }    for (int i = 1; i <= n; i++)    {        for (int j = 1; j <= n; j++)        {            cout << b[i][j] << " ";        }        cout << endl;    }}void Dijkstra(){    int dis[100] = { 0 };    bool book[100] = { 0 };    int b[100][100] = { 0 };    for (int i = 0; i <= n; i++)        for (int j = 0; j <= n; j++)            b[i][j] = a[i][j];    for (int i = 1; i <= n; i++)    {        dis[i] = a[1][i];    }    book[1] = 1;    for (int i = 1; i <= n - 1; i++)    {        int minv = INF, min = 0;        for (int i = 1; i <= n; i++)        {            if (!book[i] && minv > dis[i])            {                minv = dis[i];                   //在取最小值的过程中可以用堆优化                min = i;            }        }        book[min] = 1;        for (int j = 1; j <= n; j++)        {            if (dis[j] > dis[min] + a[min][j])            {                dis[j] = dis[min] + a[min][j];    //用最短的边对其他所有点进行优化            }        }    }    for (int i = 1; i <= n; i++)    {        cout << dis[i] << " ";    }    cout << endl;}void Bellman(){    int dis[100] = { 0 };    int b[100][100] = { 0 };    for (int i = 0; i <= n; i++)        for (int j = 0; j <= n; j++)            b[i][j] = a[i][j];    for (int i = 1; i <= n; i++)        dis[i] = INF;    dis[1] = 0;    /*for (int i = 1; i <= n; i++)    {        dis[i] = a[1][i];    }*/    for (int i = 1; i <= n - 1; i++)    {        for (int j = 1; j <= n; j++)        {            for (int k = 1; k <= n; k++)            {                if (dis[k] > dis[j] + a[j][k])                {                    dis[k] = dis[j] + a[j][k];                }            }        }    }    for (int i = 1; i <= n; i++)    {        cout << dis[i] << " ";    }    cout << endl;}void BellmanQueue(){    int dis[100] = { 0 };    int b[100][100] = { 0 };    for (int i = 0; i <= n; i++)        for (int j = 0; j <= n; j++)            b[i][j] = a[i][j];    for (int i = 1; i <= n; i++)        dis[i] = INF;    dis[1] = 0;    queue<int> que;    bool book[100] = { 0 };    que.push(1);    book[1] = 1;    while (que.size())    {        int k = que.front();        que.pop();        for (int i = 1; i <= n; i++)        {            if (dis[i] > dis[k] + b[k][i])            {                dis[i] = dis[k] + b[k][i];                if (!book[i])                {                    que.push(i);                    book[i] = 1;                }            }        }        book[k] = 0;    }    for (int i = 1; i <= n; i++)    {        cout << dis[i] << " ";    }    cout << endl;}void warshall2(){    vector<edge> G[100];    int n, m;    cin >> n >> m;    for (int i = 0; i < m; i++)    {        int p;        edge q;        cin >> p >> q.to >> q.cost;        G[p].push_back(q);    }    for (int i = 1; i <= n; i++)    {        for (int k = 1; k <= n; k++)        {            for (int j = 0; j < G[k].size(); j++)            {                edge e = G[k][j];            }        }    }    cout << "不会\n";}void Dijkstra2(){    vector<edge> G[100];    int n, m;    cin >> n >> m;    int dis[100] = { 0 };    fill(dis, dis + 100, INF);    dis[1] = 0;    for (int i = 0; i < m; i++)    {        int p;        edge q;        cin >> p >> q.to >> q.cost;        G[p].push_back(q);    }    priority_queue<P, vector<P>, greater<P> >que;    que.push(P(0, 1));    while (que.size())    {        P p= que.top(); que.pop();        for (int i = 0; i < G[p.second].size(); i++)        {            edge e = G[p.second][i];            if (dis[e.to] > dis[p.second] + e.cost)            {                dis[e.to] = dis[p.second] + e.cost;                que.push(P(dis[e.to], e.to));            }        }    }    for (int i = 1; i <= n; i++)    {        cout << dis[i] << " ";    }    cout << endl;}void Bellman2(){    edge G[100];    int n, m;    cin >> n >> m;    int dis[100] = { 0 };    fill(dis, dis + 100, INF);    dis[1] = 0;    for (int i = 0; i < m; i++)    {        cin >> G[i].from >> G[i].to >> G[i].cost;    }    for (int i = 1; i <= n - 1; i++)    {        for (int j = 0; j < m; j++)        {            dis[G[j].to] = min(dis[G[j].to], dis[G[j].from] + G[j].cost);        }    }    for (int i = 1; i <= n; i++)    {        cout << dis[i] << " ";    }    cout << endl;}int main(){    cin >> n >> m;    for(int i=0;i<=n;i++)        for (int j = 0; j <= n; j++)        {            if (i == j) a[i][j] = 0;            else a[i][j] = INF;        }    for (int i = 1; i <= m; i++)    {        int p, q, t;        cin >> p >> q >> t;        a[p][q] = t;    }    cout << "邻接矩阵:\n";    cout << "1:Floyd-warshall    2:Dijkstra    3:Bellman-Ford    4:Bellman队列优化(SPFA)\n";    cout << "邻接表\n";    cout << "5:Floyd-warshall    6:Dijkstra(堆优化)   7：Bellman-Ford\n";    int t;    while (cin >> t)    {        if (t == 1)        {            warshall();        }        else if (t == 2)        {            cout << "Dijkstra:\n";            Dijkstra();        }        else if (t == 3)        {            cout << "Bellman-Ford:\n";            Bellman();        }        else if (t == 4)        {            cout << "Bellman队列优化:\n";            BellmanQueue();        }        else if (t == 5)        {            cout << "Floyd-warshall（邻接表）:\n";            warshall2();        }        else if (t == 6)        {            cout << "Dijkstra(堆优化) \n";            Dijkstra2();        }        else if (t == 7)        {            cout << "Bellman-Ford:\n";            Bellman2();        }    }}