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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. #include <iostream>
  4. #include <vector>
  5. using namespace std;
  6.  
  7. void dfs(vector<vector<int>>& img, int x, 
  8.          int y, int oldColor, int newColor) {
  9.  
  10.     if (x < 0 || x >= img.size() || 
  11.         y < 0 || y >= img[0].size() || img[x][y] != oldColor) {
  12.               return; 
  13.     }
  14.  
  15.     // Update the color of the current pixel
  16.     img[x][y] = newColor;
  17.  
  18.     // Recursively visit all 4 connected neighbors
  19.     dfs(img, x + 1, y, oldColor, newColor); 
  20.     dfs(img, x - 1, y, oldColor, newColor); 
  21.     dfs(img, x, y + 1, oldColor, newColor); 
  22.     dfs(img, x, y - 1, oldColor, newColor); 
  23. }
  24.  
  25. vector<vector<int>> floodFill(vector<vector<int>>& img, int sr, 
  26.     int sc, int newColor) {
  27.  
  28.     // If the starting pixel already has the new color,
  29.     // no changes are needed
  30.     if (img[sr][sc] == newColor) {
  31.         return img;
  32.     }
  33.  
  34.     // Call DFS to start filling from the source pixel
  35.      // Store original color
  36.     int oldColor = img[sr][sc];
  37.     dfs(img, sr, sc, oldColor, newColor);
  38.  
  39.     return img;
  40. }
  41.  
  42. int main() {
  43.     vector<vector<int>> img = {
  44.         {1, 1, 1, 0},
  45.         {0, 1, 1, 1},
  46.         {1, 0, 1, 1}
  47.     };
  48.  
  49.     int sr = 1, sc = 2;
  50.  
  51.     int newColor = 2;        
  52.  
  53.     vector<vector<int>> result = floodFill(img, sr, sc, newColor);
  54.  
  55.     for (auto& row : result) {
  56.         for (auto& pixel : row) {
  57.             cout << pixel << " ";
  58.         }
  59.     }
  60.     return 0;
  61. }
  62.  
Success #stdin #stdout 0s 5320KB
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stdin
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Standard input is empty
stdout
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2 2 2 0 0 2 2 2 1 0 2 2
https://ideone.com/AeClV9
language:
C++ (gcc 8.3)
created:
2 hours ago
visibility:
public

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