solve missing number

Author: sora0319

missing-number/sora0319.java

@@ -0,0 +1,20 @@
+class Solution {
+    public int missingNumber(int[] nums) {
+        int result = 0;
+        int[] counts = new int[nums.length+1];
+
+        for(int n : nums){
+            counts[n] = 1;
+        }
+
+        for(int i = 0; i < counts.length; i++){
+            if(counts[i] == 0){
+                result = i;
+                break;
+            }
+        }
+
+        return result;
+    }
+}
+