645 + README

Author: Cappuccinuo

Array/645. Set Mismatch/README.md

@@ -0,0 +1,16 @@
+Time spent : 20 min(Self + see hint)
+
+GIVEN: an array
+
+RETURNS: duplicate num and missing num
+
+EXAMPLES:
+
+```
+Input: nums = [1,2,2,4]
+Output: [2,3]
+```
+
+
+
+Use the kind of vote progress. Make an integer flag to represent if the num has occured before. If flag is true, then the num is duplicate one.

Array/645. Set Mismatch/Solution.java

@@ -0,0 +1,40 @@
+// 9ms
+class Solution {
+    public int[] findErrorNums(int[] nums) {
+        int[] result = new int[2];
+        int[] numsFlag = new int[nums.length + 1];
+        for (int i = 0; i < nums.length; i++) {
+            if (numsFlag[nums[i]] == -1) {
+                result[0] = nums[i];
+            }
+            else {
+                numsFlag[nums[i]] = -1;
+            }
+        }
+        for (int i = 1; i <= numsFlag.length; i++) {
+            if (numsFlag[i] == 0) {
+                result[1] = i;
+                break;
+            }
+        }
+        return result;
+    }
+}
+
+// 58ms
+public class Solution {
+    public int[] findErrorNums(int[] nums) {
+    Map<Integer, Integer> map = new HashMap<Integer, Integer>();
+    int n = nums.length;
+    int duplicate = 0;
+    long sum = (n * (n + 1)) / 2;  
+    for (int i : nums) {
+        map.put(i, map.getOrDefault(i, 0) + 1);
+        if (map.get(i) == 2) {
+            duplicate = i;
+        }
+        sum = sum - i;
+    }
+    return new int[]{duplicate, (int)sum + duplicate};
+    }
+}

Pending/645.set-mismatch.java

@@ -104,7 +104,7 @@
 | 100  | 438  |   [Find All Anagrams in a String][438]   |     Java     |    Easy    |       2017.7.21       |                 HashMap                  |                       |
 | 101  | 599  |  [Minimum Index Sum of Two Lists][599]   |     Java     |    Easy    |       2017.7.21       |                 HashMap                  |                       |
 | 102  | 205  |        [Isomorphic Strings][205]         |     Java     |    Easy    |       2017.7.23       |                Hash Table                |       2018.1.7        |
-| 103  | 645  |           [Set Mismatch][645]            |     Java     |    Easy    |       2017.7.23       |                 HashMap                  |                       |
+| 103  | 645  |           [Set Mismatch][645]            |     Java     |    Easy    |       2017.7.23       |              HashMap, Array              |       2018.1.14       |
 | 104  | 204  |           [Count Primes][204]            |     Java     |    Easy    |       2017.7.24       |              HashMap, Math               |       2018.1.7        |
 | 105  | 290  |           [Word Pattern][290]            |     Java     |    Easy    |       2017.7.24       |                HashTable                 |       2018.1.7        |
 | 106  |  12  |          [Integer to Roman][12]          |     Java     |   Medium   |       2017.7.27       |               Math, String               |       2018.1.4        |