囚人のジレンマ

prisoner.rb

# input:
#  strategy_i - strategy of player 1, 2.
# output:
#  payoff_i - payoff rewarded to player 1, 2.

def prisoner (strategy_1, strategy_2)
    if strategy_1 == "m" 
        if strategy_2 == "m" 
            payoff_1 = -1
            payoff_2 = -1
        elsif strategy_2 == "f" 
            payoff_1 = -9
            payoff_2 = -0
        end 
    elsif strategy_1 == "f" 
        if strategy_2 == "m" 
            payoff_1 = 0 
            payoff_2 = -9
        elsif strategy_2 == "f" 
            payoff_1 = -6
            payoff_2 = -6
        end 
    end 
    return payoff_1, payoff_2
end