JAVA：劍指_Offer_03_數組中重複的數字

package 劍指offer_初級;

import java.util.HashSet;
import java.util.Set;

public class 劍指_Offer_03_數組中重複的數字 {
    class Solution {
        public int findRepeatNumber(int[] nums) {
            for(int i=0;i<nums.length;i++){
                for(int j=i+1;j<nums.length;j++){
                   if(nums[i]==nums[j]){
                       return nums[i];
                   }
                }
            }
            return -1;
        }
        public int findNumber(int[] nums) {
            Set<Integer> dic = new HashSet<>();
            for(int num : nums) {
                if(dic.contains(num)){return num;}
                dic.add(num);
            }
            return -1;
        }
    }
}