Add 1905 in c language

Author: julienChemillier

c/1905-count-sub-islands.c

@@ -0,0 +1,35 @@
+/*
+
+Space: O(n²) (due to recursives calls)
+Time: O(n²)
+*/
+
+bool dfs_test(int** grid1, int** grid2, int i, int j, int n, int m) {
+    // Test if the island in grid2 is entirely in grid1 and delete the island in grid2
+    bool ans = (grid1[i][j] == 1);
+    grid2[i][j] = 0;
+    if (i>0 && grid2[i-1][j]==1)
+        ans = dfs_test(grid1, grid2, i-1, j, n ,m) && ans;
+    if (j>0  && grid2[i][j-1]==1)
+        ans = dfs_test(grid1, grid2, i, j-1, n ,m) && ans;
+    if (i<(n-1)  && grid2[i+1][j]==1)
+        ans = dfs_test(grid1, grid2, i+1, j, n ,m) && ans;
+    if (j<(m-1)  && grid2[i][j+1]==1)
+        ans = dfs_test(grid1, grid2, i, j+1, n ,m) && ans;
+    return ans;
+}
+
+int countSubIslands(int** grid1, int grid1Size, int* grid1ColSize, int** grid2, int grid2Size, int* grid2ColSize){
+    int cpt=0;
+    for (int i=0; i<grid1Size; i++) {
+        for (int j=0; j<grid1ColSize[i]; j++) {
+            if (grid2[i][j]==1) {
+                // Test if the island in grid2 is contained in an island in grid1
+                if (dfs_test(grid1, grid2, i, j, grid1Size, grid1ColSize[i])){
+                    cpt++;
+                }
+            }
+        }
+    }
+    return cpt;
+}