testcases:
  - name: "testcase 1"
    inputs:
    - 1 : [1, 2, 2, 3, 4, 4, 3]
    output: 
    - 1 : True
  - name: "testcase 2"
    inputs:
    - 1: [18, 21, 21, 47, 20, 21, 47]
    output:
    - 1 : False
  - name: "testcase 3"
    inputs:
    - 1: [25, 4, 67, 2, 3, 3, 2]
    output:
    - 1 : False
  - name: "testcase 4"
    inputs:
    - 1: [1, 2, 2, 3, null, null, 3]
    output:
    - 1 : True
  - name: "testcase 5"
    inputs:
    - 1: [1, 2, 2, null, 3, null, 3]
    output:
    - 1 : False
  - name: "testcase 6"
    inputs:
    - 1: [1, 2, 2, null, 3, 3, null, 4, 5, 5, 4]
    output:
    - 1 : True
  - name: "testcase 7"
    inputs:
    - 1: [1, 1, 1]
    output:
    - 1 : True
  - name: "testcase 8"
    inputs:
    - 1: [2, null, 1]
    output:
    - 1 : False
  - name: "testcase 9"
    inputs:
    - 1: [100, 200, 200, null, 300, 400, null]
    output:
    - 1 : False