Merge pull request #238 from paurush11/master

Rotten Oranges

Author: smv1999

Data Structures/Graphs/RottenOranges.cpp

@@ -0,0 +1,73 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+#define f(i,a,b) for(int i = a;i<b;i++)
+class Solution
+{
+    public:
+    //Function to find minimum time required to rot all oranges.
+    void solve(int r, int c, queue<pair<int,int>>&q, vector<vector<int>>&grid){
+        int rr[4] = {-1,1,0,0};
+        int cc[4] = {0,0,-1,1};
+        for(int i = 0;i<4;i++){
+            int nr = r + rr[i];
+            int nc = c + cc[i];
+
+            if(nr<0 || nc<0 || nr>=grid.size()|| nc>=grid[0].size())continue;
+            if(grid[nr][nc] == 1){
+                grid[nr][nc] = 2;
+                q.push({nr,nc});
+            }
+
+        }
+    }
+    int orangesRotting(vector<vector<int>>& grid) {
+        queue<pair<int,int>>q;
+        f(i,0,grid.size()){
+            f(j,0,grid[0].size()){
+                if(grid[i][j] == 2){
+                    q.push({i,j});
+                }
+            }
+        }
+        int timer = -1;
+        while(!q.empty()){
+            int k = q.size();
+            while(k--){
+                int r = q.front().first;
+                int c = q.front().second;
+                q.pop();
+                solve(r,c,q,grid);
+            }
+            timer++;
+        }
+        for(auto i: grid){
+            for(auto j :i){
+                if(j == 1)return -1;
+            }
+
+        }
+        return timer;
+
+
+    }
+};
+
+int main(){
+	int tc;
+	cin >> tc;
+	while(tc--){
+		int n, m;
+		cin >> n >> m;
+		vector<vector<int>>grid(n, vector<int>(m, -1));
+		for(int i = 0; i < n; i++){
+			for(int j = 0; j < m; j++){
+				cin >> grid[i][j];
+			}
+		}
+		Solution obj;
+		int ans = obj.orangesRotting(grid);
+		cout << ans << "\n";
+	}
+	return 0;
+}  //