Snakes and Ladders Graph problem

Program's_Contributed_By_Contributors/C++_Programs/Graph/Snakes and Ladders.cpp

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+// Link to Problem : https://www.hackerrank.com/challenges/the-quickest-way-up/problem
+
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+string ltrim(const string &);
+string rtrim(const string &);
+vector<string> split(const string &);
+
+/*
+ * Complete the 'quickestWayUp' function below.
+ *
+ * The function is expected to return an INTEGER.
+ * The function accepts following parameters:
+ *  1. 2D_INTEGER_ARRAY ladders
+ *  2. 2D_INTEGER_ARRAY snakes
+ */
+
+struct Node{
+    int x,dist;
+};
+
+int bfs(int src, map<int, int> m){
+    vector<int> visited(100,0);
+    visited[0]=1;
+    queue<Node> q;
+    q.push({0,0});
+    Node temp;
+    int x,d;
+    int min_dist=-1;
+    while(q.empty()==false){
+        temp = q.front();
+        q.pop();
+        x = temp.x;
+        // y = temp.y;
+        d = temp.dist;
+
+        if(x==99){
+            min_dist = d;
+            return min_dist;
+        }
+
+        for(int i=x+1;i<=(x+6) && i<100;i++){
+            if(visited[i]==false){
+                if(m.find(i)==m.end()){
+                    q.push({i,d+1});
+                }
+                else{
+                    q.push({m[i], d+1});
+                }
+                visited[i]=true;
+            }
+        }
+    }
+    return min_dist;
+}
+
+int quickestWayUp(vector<vector<int>> ladders, vector<vector<int>> snakes) {
+    map<int,int > m;
+    for(int i=0;i<ladders.size();i++)
+        m[ladders[i][0]-1] = ladders[i][1]-1;
+    for(int i=0;i<snakes.size();i++)
+        m[snakes[i][0]-1] = snakes[i][1]-1;
+
+    int ans=bfs(0, m);
+    return ans;
+}
+
+int main()
+{
+    ofstream fout(getenv("OUTPUT_PATH"));
+
+    string t_temp;
+    getline(cin, t_temp);
+
+    int t = stoi(ltrim(rtrim(t_temp)));
+
+    for (int t_itr = 0; t_itr < t; t_itr++) {
+        string n_temp;
+        getline(cin, n_temp);
+
+        int n = stoi(ltrim(rtrim(n_temp)));
+
+        vector<vector<int>> ladders(n);
+
+        for (int i = 0; i < n; i++) {
+            ladders[i].resize(2);
+
+            string ladders_row_temp_temp;
+            getline(cin, ladders_row_temp_temp);
+
+            vector<string> ladders_row_temp = split(rtrim(ladders_row_temp_temp));
+
+            for (int j = 0; j < 2; j++) {
+                int ladders_row_item = stoi(ladders_row_temp[j]);
+
+                ladders[i][j] = ladders_row_item;
+            }
+        }
+
+        string m_temp;
+        getline(cin, m_temp);
+
+        int m = stoi(ltrim(rtrim(m_temp)));
+
+        vector<vector<int>> snakes(m);
+
+        for (int i = 0; i < m; i++) {
+            snakes[i].resize(2);
+
+            string snakes_row_temp_temp;
+            getline(cin, snakes_row_temp_temp);
+
+            vector<string> snakes_row_temp = split(rtrim(snakes_row_temp_temp));
+
+            for (int j = 0; j < 2; j++) {
+                int snakes_row_item = stoi(snakes_row_temp[j]);
+
+                snakes[i][j] = snakes_row_item;
+            }
+        }
+
+        int result = quickestWayUp(ladders, snakes);
+
+        fout << result << "\n";
+    }
+
+    fout.close();
+
+    return 0;
+}
+
+string ltrim(const string &str) {
+    string s(str);
+
+    s.erase(
+        s.begin(),
+        find_if(s.begin(), s.end(), not1(ptr_fun<int, int>(isspace)))
+    );
+
+    return s;
+}
+
+string rtrim(const string &str) {
+    string s(str);
+
+    s.erase(
+        find_if(s.rbegin(), s.rend(), not1(ptr_fun<int, int>(isspace))).base(),
+        s.end()
+    );
+
+    return s;
+}
+
+vector<string> split(const string &str) {
+    vector<string> tokens;
+
+    string::size_type start = 0;
+    string::size_type end = 0;
+
+    while ((end = str.find(" ", start)) != string::npos) {
+        tokens.push_back(str.substr(start, end - start));
+
+        start = end + 1;
+    }
+
+    tokens.push_back(str.substr(start));
+
+    return tokens;
+}