动态规划多段图的最短路径问题c++

以下是动态规划多段图的最短路径问题的C++代码实现：

#include <iostream>
#include <cstring>
using namespace std;

const int N = 110, INF = 0x3f3f3f3f;

int n, m;
int g[N][N], dist[N];
bool st[N];

int dijkstra()
{
    memset(dist, 0x3f, sizeof dist);
    dist[1] = 0;

    for (int i = 0; i < n; i ++ )
    {
        int t = -1;
        for (int j = 1; j <= n; j ++ )
            if (!st[j] && (t == -1 || dist[t] > dist[j]))
                t = j;

        st[t] = true;

        for (int j = 1; j <= n; j ++ )
            dist[j] = min(dist[j], dist[t] + g[t][j]);
    }

    return dist[n];
}

int main()
{
    cin >> n >> m;

    memset(g, 0x3f, sizeof g);

    while (m -- )
    {
        int a, b, c;
        cin >> a >> b >> c;
        g[a][b] = min(g[a][b], c);
    }

    for (int i = 1; i <= n; i ++ )
        for (int j = i + 1; j <= n; j ++ )
            for (int k = i; k < j; k ++ )
                if (g[i][j] != INF)
                    g[i][j] = min(g[i][j], g[i][k] + g[k][j]);

    cout << dijkstra() << endl;

    return 0;
}