存在重复元素
解法一:HashSet判重
import java.util.HashSet;
import java.util.Set;
public class LeetCode_217 {
public static boolean containsDuplicate(int[] nums) {
Set<Integer> notRepeatedNums = new HashSet<>();
for (int num : nums) {
if (!notRepeatedNums.add(num)) {
return true;
}
}
return false;
}
public static void main(String[] args) {
int[] nums = new int[]{1, 2, 3, 1};
System.out.println(containsDuplicate(nums));
}
}