From 8989118332cd8d1064028820fae4f701c739dc46 Mon Sep 17 00:00:00 2001
From: Ana Musib <ana1998musib@gmail.com>
Date: Mon, 31 Aug 2020 06:58:27 +0530
Subject: [PATCH] Update _373.java

---
 .../java/com/fishercoder/solutions/_373.java  | 90 ++++++++-----------
 1 file changed, 38 insertions(+), 52 deletions(-)

diff --git a/src/main/java/com/fishercoder/solutions/_373.java b/src/main/java/com/fishercoder/solutions/_373.java
index 2316ca5841..ddc80a698d 100644
--- a/src/main/java/com/fishercoder/solutions/_373.java
+++ b/src/main/java/com/fishercoder/solutions/_373.java
@@ -6,60 +6,46 @@
 import java.util.Queue;
 
 public class _373 {
-    public static class Solution1 {
 
-        final int[][] neighbors = new int[][]{{0, 1}, {1, 0}};
-
-        public List<int[]> kSmallestPairs(int[] nums1, int[] nums2, int k) {
-            List<int[]> result = new ArrayList<>();
-            if (nums1 == null
-                    || nums2 == null
-                    || k == 0
-                    || nums1.length == 0
-                    || nums2.length == 0) {
-                return result;
-            }
-            Queue<Pair> meanHeap = new PriorityQueue<>();
-            meanHeap.offer(new Pair(0, 0, nums1[0] + nums2[0]));
-            boolean[][] visited = new boolean[nums1.length][nums2.length];
-            visited[0][0] = true;//we start form (0,0), so mark it as visited
-            while (k > 0 && !meanHeap.isEmpty()) {
-                Pair pair = meanHeap.poll();
-                result.add(new int[]{nums1[pair.row], nums2[pair.col]});
-                k--;
-                for (int[] neighbor : neighbors) {
-                    int nextRow = pair.row + neighbor[0];
-                    int nextCol = pair.col + neighbor[1];
-                    if (nextRow < 0
-                            || nextCol < 0
-                            || nextRow >= nums1.length
-                            || nextCol >= nums2.length
-                            || visited[nextRow][nextCol]) {
-                        continue;
-                    }
-                    visited[nextRow][nextCol] = true;
-                    meanHeap.offer(new Pair(nextRow, nextCol, nums1[nextRow] + nums2[nextCol]));
-                }
-            }
-
-            return result;
-        }
-
-        class Pair implements Comparable<Pair> {
-            int row;
-            int col;
-            int sum;
-
-            public Pair(int row, int col, int sum) {
-                this.row = row;
-                this.col = col;
-                this.sum = sum;
-            }
-
-            @Override
-            public int compareTo(Pair that) {
-                return this.sum - that.sum;
+  public class Solution {
+    
+    int[][] dirs = {{0,1},{1,0},{1,1}};
+    public List<List<Integer>> kSmallestPairs(int[] nums1, int[] nums2, int k) {
+        
+        List<List<Integer>> result = new ArrayList<>();
+        
+        // EDGE CASE
+        if(nums1==null || nums2==null || nums1.length==0 || nums2.length==0) return result;
+        
+        // visited array
+        boolean[][] visited = new boolean[nums1.length][nums2.length];
+        
+        // Min Heap
+        PriorityQueue<int[]> pq = new PriorityQueue<>((a,b)->{
+            return  ( a[0]+a[1] ) - ( b[0]+b[1] ) ;
+        });
+        
+        int[] temp = new int[]{nums1[0],nums2[0],0,0};
+        pq.add(temp);
+        visited[0][0]= true;
+        
+        while(!pq.isEmpty()){
+            int[] arr = pq.poll();
+            List<Integer> ls = new ArrayList<>();
+            ls.add(arr[0]);ls.add(arr[1]);
+            result.add(ls);
+            
+            if(result.size()==k) break;
+            int i=arr[2],j=arr[3];
+            
+            for(int[] dir : dirs){
+                int dx=i+dir[0],dy=j+dir[1];
+                if(dx<0 || dx>=nums1.length || dy<0 || dy>=nums2.length || visited[dx][dy]) continue;
+                pq.add(new int[]{nums1[dx],nums2[dy],dx,dy});   
+                visited[dx][dy] = true;
             }
         }
+        return result;
     }
+  }
 }