<p>You are given an <strong>undirected weighted</strong> <strong>connected</strong> graph containing <code>n</code> nodes labeled from <code>0</code> to <code>n - 1</code>, and an integer array <code>edges</code> where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, w<sub>i</sub>]</code> indicates that there is an edge between nodes <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> with weight <code>w<sub>i</sub></code>.</p>

<p>Some edges have a weight of <code>-1</code> (<code>w<sub>i</sub> = -1</code>), while others have a <strong>positive</strong> weight (<code>w<sub>i</sub> &gt; 0</code>).</p>

<p>Your task is to modify <strong>all edges</strong> with a weight of <code>-1</code> by assigning them <strong>positive integer values </strong>in the range <code>[1, 2 * 10<sup>9</sup>]</code> so that the <strong>shortest distance</strong> between the nodes <code>source</code> and <code>destination</code> becomes equal to an integer <code>target</code>. If there are <strong>multiple</strong> <strong>modifications</strong> that make the shortest distance between <code>source</code> and <code>destination</code> equal to <code>target</code>, any of them will be considered correct.</p>

<p>Return <em>an array containing all edges (even unmodified ones) in any order if it is possible to make the shortest distance from </em><code>source</code><em> to </em><code>destination</code><em> equal to </em><code>target</code><em>, or an <strong>empty array</strong> if it&#39;s impossible.</em></p>

<p><strong>Note:</strong> You are not allowed to modify the weights of edges with initial positive weights.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<p><strong class="example"><img alt="" src="https://assets.leetcode.com/uploads/2023/04/18/graph.png" style="width: 300px; height: 300px;" /></strong></p>

<pre>
<strong>Input:</strong> n = 5, edges = [[4,1,-1],[2,0,-1],[0,3,-1],[4,3,-1]], source = 0, destination = 1, target = 5
<strong>Output:</strong> [[4,1,1],[2,0,1],[0,3,3],[4,3,1]]
<strong>Explanation:</strong> The graph above shows a possible modification to the edges, making the distance from 0 to 1 equal to 5.
</pre>

<p><strong class="example">Example 2:</strong></p>

<p><strong class="example"><img alt="" src="https://assets.leetcode.com/uploads/2023/04/18/graph-2.png" style="width: 300px; height: 300px;" /></strong></p>

<pre>
<strong>Input:</strong> n = 3, edges = [[0,1,-1],[0,2,5]], source = 0, destination = 2, target = 6
<strong>Output:</strong> []
<strong>Explanation:</strong> The graph above contains the initial edges. It is not possible to make the distance from 0 to 2 equal to 6 by modifying the edge with weight -1. So, an empty array is returned.
</pre>

<p><strong class="example">Example 3:</strong></p>

<p><strong class="example"><img alt="" src="https://assets.leetcode.com/uploads/2023/04/19/graph-3.png" style="width: 300px; height: 300px;" /></strong></p>

<pre>
<strong>Input:</strong> n = 4, edges = [[1,0,4],[1,2,3],[2,3,5],[0,3,-1]], source = 0, destination = 2, target = 6
<strong>Output:</strong> [[1,0,4],[1,2,3],[2,3,5],[0,3,1]]
<strong>Explanation:</strong> The graph above shows a modified graph having the shortest distance from 0 to 2 as 6.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= n &lt;= 100</code></li>
	<li><code><font face="monospace">1 &lt;= edges.length &lt;= n * (n - 1) / 2</font></code></li>
	<li><code>edges[i].length == 3</code></li>
	<li><code>0 &lt;= a<sub>i</sub>, b<sub>i&nbsp;</sub>&lt;&nbsp;n</code></li>
	<li><code><font face="monospace">w<sub>i</sub>&nbsp;= -1&nbsp;</font></code>or <code><font face="monospace">1 &lt;= w<sub>i&nbsp;</sub>&lt;= 10<sup><span style="font-size: 10.8333px;">7</span></sup></font></code></li>
	<li><code>a<sub>i&nbsp;</sub>!=&nbsp;b<sub>i</sub></code></li>
	<li><code>0 &lt;= source, destination &lt; n</code></li>
	<li><code>source != destination</code></li>
	<li><code><font face="monospace">1 &lt;= target &lt;= 10<sup>9</sup></font></code></li>
	<li>The graph is connected, and there are no self-loops or repeated edges</li>
</ul>

class Solution {
public:
    vector<int> djik(int n,int s,int de,unordered_map<int,vector<vector<int>>>&mp,unordered_set<int>&st){
        vector<int>dist(n,2e9);
        dist[s]=0;
        queue<vector<int>>q;
        q.push({s,0});
        while(q.size()){
            auto it=q.front();
            q.pop();
            int x=it[0];
            int wt=it[1];
            for(auto it:mp[x]){
                if(dist[it[0]]>wt+it[1]){
                    dist[it[0]]=wt+(it[1]);
                    q.push({it[0],dist[it[0]]});
                }
            }
        }
        return dist;
    }
    vector<vector<int>> modifiedGraphEdges(int n, vector<vector<int>>& edges, int s, int de, int target) {
        int d=0;
        unordered_map<int,vector<vector<int>>>mp;
        unordered_set<int>st;
        //make all -1 to 1
        for(int i=0;i<edges.size();i++){
            if(edges[i][2]>0){
        mp[edges[i][0]].push_back({edges[i][1],edges[i][2]});
        mp[edges[i][1]].push_back({edges[i][0],edges[i][2]});
            }
        else st.insert(i);
        }
        vector<vector<int>> temp=edges;
        vector<int> fo=djik(n,s,de,mp,st);
        if(fo[de]<target)return {};
        // if(fo[de]>target)return {};
        int dif=target-fo[de];
        for(auto it:st){
            edges[it][2]=target+1;
        }
        if(dif==0){
        return edges;
        }
        for(auto it:st){
            auto &x=edges[it];
            mp[x[0]].push_back({x[1],1});
            mp[x[1]].push_back({x[0],1});
            x[2]=1;
            vector<int>c=djik(n,s,de,mp,st);
            if(c[de]<=target){
                edges[it][2]+=target-c[de];
                return edges;
            }
        }
        return {};
        /*
        vector<int> fn=djik(n,de,de,mp,st);
        vector<int>vis(edges.size(),0);
        for(int i=0;i<edges.size();i++){
            vector<int>&x=edges[i];
    if(fo[x[0]]+fn[x[1]]+x[2]==fo[de] || fo[x[1]]+fn[x[0]]+x[2]==fo[de])
            vis[i]=1;
        }
        // After changing all to 1 ,If min dist is more not possible
        // for(int it:vis)cout<<"%"<<it;
        // cout<<endl;
        // cout<<"&&"<<endl;
        bool c=false;
        // In the found path make target and all other 2e9
        for(int i=0;i<edges.size();i++){
            if(st.count(i) && vis[i]==1){
                // cout<<"$"<<edges[i][1]<<endl;
                edges[i][2]+=dif;
                dif=0;
                c=true;
            }
            else if(st.count(i))edges[i][2]=target+1;
        }
            for(int i=0;i<edges.size();i++){
            // cout<<edges[i][0]<<" "<<edges[i][1]<<" "<<edges[i][2]<<endl;
            }
            // Make another map of new edges to find any other shorter
            //path exists
        unordered_map<int,vector<vector<int>>>lk;
        // lk=mp;
        for(int i=0;i<edges.size();i++){
        lk[edges[i][0]].push_back({edges[i][1],edges[i][2]});
        lk[edges[i][1]].push_back({edges[i][0],edges[i][2]});
        }
        // After adding diff if shortest is target
        vector<int>q=djik(n,s,de,lk,st);
        // cout<<q[de]<<"*"<<endl;
        if(q[de]==target)return edges;
        // edges=temp;
        unordered_map<int,vector<vector<int>>>mp2;
        for(int i=0;i<edges.size();i++){
            // cout<<edges[i][0]<<edges[i][1]<<edges[i][2]<<endl;
            mp2[edges[i][0]].push_back({edges[i][1],edges[i][2]});
            mp2[edges[i][1]].push_back({edges[i][0],edges[i][2]});
        }
        vector<int>ddi=djik(n,s,de,mp2,st);
        fo=djik(n,s,de,mp2,st);
        fn=djik(n,de,de,mp2,st);
        vector<int>viss(edges.size(),0);
        for(int i=0;i<edges.size();i++){
            // cout<<edges[i][0]<<edges[i][1]<<edges[i][2]<<endl;
            vector<int>&x=edges[i];
    if(fo[x[0]]+fn[x[1]]+x[2]==fo[de] || fo[x[1]]+fn[x[0]]+x[2]==fo[de])
            viss[i]=1;
        }
        // for(int it:viss)cout<<it<<"%";
        // cout<<endl;
        // cout<<"&&"<<endl;
        // cout<<ddi[de]<<"&&&"<<endl;
        if(ddi[de]==target)return edges;
        else if(ddi[de]>target)return {};
        else if(target>ddi[de]){
            bool f=false;
            if(!c)return {};
            int dif=target-ddi[de];
            for(int i=0;i<edges.size();i++){
                if(st.count(i) && viss[i]==1){
                    edges[i][2]+=dif;
                    dif=0;
                    f=true;
                }
                else if(st.count(i)){
                    edges[i][2]=target+1;
                }
            }
            unordered_map<int,vector<vector<int>>>kk;
            for(int i=0;i<edges.size();i++){
            // cout<<edges[i][0]<<edges[i][1]<<edges[i][2]<<endl;
            kk[edges[i][0]].push_back({edges[i][1],edges[i][2]});
            kk[edges[i][1]].push_back({edges[i][0],edges[i][2]});
        }
            vector<int>t=djik(n,s,de,kk,st);
            for(auto it:edges){
                // cout<<it[0]<<" "<<it[1]<<" "<<it[2]<<endl;
            }
            // cout<<t[de]<<endl;
            // for(int it:t)cout<<it<<" ";
            if(t[de]==target)return edges;
            else return {};
        }
        if(!c)return {};
        return edges;
        */
    }
};
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