commit

Author: 王俊超

.idea/modules.xml

@@ -0,0 +1,39 @@
+/**
+ * @author: wangjunchao(王俊超)
+ * @time: 2018-10-10 14:02
+ **/
+public class Solution {
+    public int missingNumber(int[] nums) {
+
+        if (nums == null || nums.length < 1) {
+            throw new IllegalArgumentException("array should contain at least one element");
+        }
+
+        for (int i = 0; i < nums.length; i++) {
+            // 只会存在一个大于nums.length的数，将其放在数组最后一个位置
+            if (nums[i] > nums.length) {
+                swap(nums, i, nums.length - 1);
+            }
+
+            // 交换位置，直到nums[i] = i
+            while (nums[i] != i && nums[i] < nums.length) {
+                swap(nums, i, nums[i]);
+            }
+        }
+
+        // 找出丢失的元素
+        for (int i = 0; i < nums.length; i++) {
+            if (nums[i] != i) {
+                return i;
+            }
+        }
+
+        return nums.length;
+    }
+
+    private void swap(int[] nums, int x, int y) {
+        int temp = nums[x];
+        nums[x] = nums[y];
+        nums[y] = temp;
+    }
+}

【268】【Missing Number】/src/Solution.java

@@ -0,0 +1,21 @@
+import java.util.Arrays;
+
+/**
+ * @author: wangjunchao(王俊超)
+ * @time: 2018-10-10 14:14
+ **/
+public class Test {
+    public static void main(String[] args) {
+        Solution solution = new Solution();
+
+        missingNumber(solution, new int[]{0});
+        missingNumber(solution, new int[]{3, 0, 1});
+        missingNumber(solution, new int[]{9, 6, 4, 2, 3, 5, 7, 0, 1});
+        missingNumber(solution, new int[]{8, 6, 4, 2, 3, 5, 7, 0, 1});
+    }
+
+    private static void missingNumber(Solution solution, int[] array) {
+        System.out.println(solution.missingNumber(array));
+        System.out.println(Arrays.toString(array));
+    }
+}