Solve Problem 986 - Interval List Intersection

Author: hieu

src/contest/ReadMe.java

@@ -14,8 +14,8 @@ public class ReadMe {
     // greedy:              1354[!]     1353[x]     1338[v]
     // stack:               1190[!]     975[x]      1381[v]
     // binary search:       1351[v]     1337[v]     1292[!]
-    // 2 pointers:          1248[*]     1234[v]     986
-    // sliding window:      1208[v]     1040[!]     995
+    // 2 pointers:          1248[*]     1234[v]     986[v]
+    // sliding window:      1208[v]     1040[!]     995[!]
     // linked-list:         1290[v]     1019[!]     876
     // union-find:          1202[v]     924[v]      947
     // heap:                1054[!]     882[!]      864

src/intervals/Problem986_IntervalListIntersection.java

@@ -0,0 +1,27 @@
+package intervals;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Problem986_IntervalListIntersection {
+    public int[][] intervalIntersection(int[][] A, int[][] B) {
+        if(A == null || A.length == 0 || B == null || B.length == 0)
+            return new int[][]{};
+        List<int[]> res = new ArrayList<>();
+
+        int i = 0, j = 0;
+        int startMax, endMin;
+        while(i < A.length && j < B.length){
+            startMax = Math.max(A[i][0], B[j][0]);
+            endMin = Math.min(A[i][1], B[j][1]);
+
+            if(endMin >= startMax)
+                res.add(new int[]{startMax, endMin});
+
+            if(A[i][1] == endMin) i++;
+            if(B[j][1] == endMin) j++;
+        }
+
+        return res.toArray(new int[res.size()][2]);
+    }
+}

src/intervals/ReadMe.java

@@ -0,0 +1,20 @@
+package intervals;
+
+public class ReadMe {
+
+    // Merge 2 intervals:
+
+    // [a0, a1]
+    // [b0, b1]
+
+    /*
+        int startMax = Math.max(a0, b0);
+        int endMin = Math.min(a1, b1);
+
+        if (endMin >= startMax) res.add(new int[] {startMax, endMin});
+
+        if (a1 == endMin); // ... increase a
+        if (b1 == endMin); // ... increase b
+     */
+
+}