13. Cycle Detection Introduction

Easy

Problem Statement

Detect whether there is a cycle in an undirected graph. (Introductory concept)

Examples

1Example 1

Input:

{
  "V": 4,
  "adj": [
    [
      1
    ],
    [
      0,
      2,
      3
    ],
    [
      1,
      3
    ],
    [
      1,
      2
    ]
  ]
}

Output:

true

2Example 2

Input:

{
  "V": 3,
  "adj": [
    [
      1
    ],
    [
      0,
      2
    ],
    [
      1
    ]
  ]
}

Output:

false

3Example 3

Input:

{
  "V": 5,
  "adj": [
    [
      1
    ],
    [
      0,
      2
    ],
    [
      1,
      3
    ],
    [
      2,
      4
    ],
    [
      3
    ]
  ]
}

Output:

false