add 1271

Author: fishercoder1534

README.md

@@ -11,6 +11,7 @@ _If you like this project, please leave me a star._ ★
 |1282|[Group the People Given the Group Size They Belong To](https://leetcode.com/problems/group-the-people-given-the-group-size-they-belong-to/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1282.java) |  |  | |Medium||
 |1281|[Subtract the Product and Sum of Digits of an Integer](https://leetcode.com/problems/subtract-the-product-and-sum-of-digits-of-an-integer/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1281.java) |  |  | |Easy||
 |1277|[Count Square Submatrices with All Ones](https://leetcode.com/problems/count-square-submatrices-with-all-ones/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1277.java) |  |  | |Medium||
+|1271|[Hexspeak](https://leetcode.com/problems/hexspeak/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1271.java) |  |  | |Easy||
 |1267|[Count Servers that Communicate](https://leetcode.com/problems/count-servers-that-communicate/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1267.java) |  |  | |Medium||
 |1266|[Minimum Time Visiting All Points](https://leetcode.com/problems/minimum-time-visiting-all-points/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1266.java) |  |  | |Easy||
 |1260|[Shift 2D Grid](https://leetcode.com/problems/shift-2d-grid/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1260.java) |  |  | [:tv:](https://www.youtube.com/watch?v=9hBcARSiU0s)|Easy||

src/main/java/com/fishercoder/solutions/_1271.java

@@ -0,0 +1,50 @@
+package com.fishercoder.solutions;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * 1271. Hexspeak
+ *
+ * A decimal number can be converted to its Hexspeak representation by first converting it to an uppercase hexadecimal string,
+ * then replacing all occurrences of the digit 0 with the letter O, and the digit 1 with the letter I.
+ * Such a representation is valid if and only if it consists only of the letters in the set {"A", "B", "C", "D", "E", "F", "I", "O"}.
+ * Given a string num representing a decimal integer N, return the Hexspeak representation of N if it is valid, otherwise return "ERROR".
+ *
+ * Example 1:
+ * Input: num = "257"
+ * Output: "IOI"
+ * Explanation:  257 is 101 in hexadecimal.
+ *
+ * Example 2:
+ * Input: num = "3"
+ * Output: "ERROR"
+ *
+ * Constraints:
+ * 1 <= N <= 10^12
+ * There are no leading zeros in the given string.
+ * All answers must be in uppercase letters.
+ * */
+public class _1271 {
+    public static class Solution1 {
+        public String toHexspeak(String num) {
+            long numInt = Long.parseLong(num);
+            String hexString = Long.toHexString(numInt);
+            StringBuilder sb = new StringBuilder();
+            Set<Character> set = new HashSet<>(Arrays.asList('A', 'B', 'C', 'D', 'E', 'F', '1', '0', 'a', 'b', 'c', 'd', 'e', 'f'));
+            for (char c : hexString.toCharArray()) {
+                if (!set.contains(c)) {
+                    return "ERROR";
+                } else if (c == '1') {
+                    sb.append("I");
+                } else if (c == '0') {
+                    sb.append("O");
+                } else {
+                    sb.append(Character.toUpperCase(c));
+                }
+            }
+            return sb.toString();
+        }
+    }
+}

src/test/java/com/fishercoder/_1271Test.java

@@ -0,0 +1,37 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._1271;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _1271Test {
+    private static _1271.Solution1 solution1;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _1271.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        assertEquals("IOI", solution1.toHexspeak("257"));
+    }
+
+    @Test
+    public void test2() {
+        assertEquals("ERROR", solution1.toHexspeak("3"));
+    }
+
+    @Test
+    public void test3() {
+        assertEquals("ERROR", solution1.toHexspeak("619879596177"));
+    }
+
+    @Test
+    public void test4() {
+        assertEquals("AEIDBCDIBC", solution1.toHexspeak("747823223228"));
+    }
+
+}