Blind 75

Contains Duplicate

Problem
LC 217
Category
Array
File
blind75_LC217ContainsDuplicate.java
Path
pkg5leetcode/blind75/blind75_LC217ContainsDuplicate.java
Package
pkg5leetcode.blind75
Command
java pkg5leetcode/blind75/blind75_LC217ContainsDuplicate.java
Approach
HashSet detects repeated values.
Complexity
Time O(n), Space O(n)

LeetCode solutions

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pkg5leetcode/blind75/blind75_LC217ContainsDuplicate.java
1package pkg5leetcode.blind75;2 3/*4 * Contains Duplicate | LC 2175 * APPROACH: HashSet detects repeated values.6 * COMPLEXITY: Time O(n), Space O(n)7 */8import java.util.*;9 10public class blind75_LC217ContainsDuplicate {11    static boolean containsDuplicate(int[] nums) {12        Set<Integer> seen = new HashSet<>();13        for (int x : nums) if (!seen.add(x)) return true;14        return false;15    }16 17    public static void main(String[] args) {18        check(containsDuplicate(new int[]{1, 2, 3, 1}), "case1");19        check(!containsDuplicate(new int[]{1, 2, 3, 4}), "case2");20        System.out.println("all tests passed");21    }22 23    static void check(boolean cond, String name) {24        if (!cond) throw new AssertionError("FAILED: " + name);25        System.out.println("  PASS " + name);26    }27}