add skeleton for 1237

Author: fishercoder1534

README.md

@@ -28,6 +28,7 @@ Your ideas/fixes/algorithms are more than welcome!
 |  #  |      Title     |   Solutions   | Time          | Space         | Video  | Difficulty  | Tag                   
 |-----|----------------|---------------|---------------|---------------|--------|-------------|-------------
 |1252|[Cells with Odd Values in a Matrix](https://leetcode.com/problems/cells-with-odd-values-in-a-matrix/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1252.java) | O(m*n + k) | O(m*n) | |Easy||
+|1237|[Find Positive Integer Solution for a Given Equation](https://leetcode.com/problems/find-positive-integer-solution-for-a-given-equation/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1237.java) | O(?) | O(?) | |Easy||
 |1207|[Unique Number of Occurrences](https://leetcode.com/problems/unique-number-of-occurrences/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1207.java) | O(n) | O(1) | |Easy||
 |1160|[Find Words That Can Be Formed by Characters](https://leetcode.com/problems/find-words-that-can-be-formed-by-characters/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1160.java) | O(n) | O(m) | |Easy||
 |1154|[Day of the Year](https://leetcode.com/problems/day-of-the-year/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1154.java) | O(1) | O(1) | |Easy||

src/main/java/com/fishercoder/solutions/_1237.java

@@ -0,0 +1,57 @@
+package com.fishercoder.solutions;
+
+import java.util.List;
+
+/**
+ * 1237. Find Positive Integer Solution for a Given Equation
+ *
+ * Given a function  f(x, y) and a value z, return all positive integer pairs x and y where f(x,y) == z.
+ * The function is constantly increasing, i.e.:
+ *
+ * f(x, y) < f(x + 1, y)
+ * f(x, y) < f(x, y + 1)
+ * The function interface is defined like this:
+ *
+ * interface CustomFunction {
+ * public:
+ *   // Returns positive integer f(x, y) for any given positive integer x and y.
+ *   int f(int x, int y);
+ * };
+ * For custom testing purposes you're given an integer function_id and a target z as input,
+ * where function_id represent one function from an secret internal list, on the examples you'll know only two functions from the list.
+ * You may return the solutions in any order.
+ *
+ * Example 1:
+ * Input: function_id = 1, z = 5
+ * Output: [[1,4],[2,3],[3,2],[4,1]]
+ * Explanation: function_id = 1 means that f(x, y) = x + y
+ *
+ * Example 2:
+ * Input: function_id = 2, z = 5
+ * Output: [[1,5],[5,1]]
+ * Explanation: function_id = 2 means that f(x, y) = x * y
+ *
+ * Constraints:
+ * 1 <= function_id <= 9
+ * 1 <= z <= 100
+ * It's guaranteed that the solutions of f(x, y) == z will be on the range 1 <= x, y <= 1000
+ * It's also guaranteed that f(x, y) will fit in 32 bit signed integer if 1 <= x, y <= 1000
+ */
+public class _1237 {
+
+    // This is the custom function interface.
+    // You should not implement it, or speculate about its implementation
+    interface CustomFunction {
+        // Returns f(x, y) for any given positive integers x and y.
+        // Note that f(x, y) is increasing with respect to both x and y.
+        // i.e. f(x, y) < f(x + 1, y), f(x, y) < f(x, y + 1)
+        public int f(int x, int y);
+    }
+
+    public static class Solution1 {
+        public List<List<Integer>> findSolution(CustomFunction customfunction, int z) {
+            return null;
+        }
+    }
+
+}