number baseball game

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Required Implementation list

• [1] enter numbers
  • check if numbers are valid
    • is size 3?
    • is all characters are one digit numbers (0~9) ?
  • if input number is not valid, re-enter until valid number
• [2] generate computer's numbers
  • check if generated numbers are valid
    • is there any same numbers?
• [3] decide result of the game
• [4] decide repeat or terminate game