% This program does the subway interview
clear
trials=10000;
patience=1000;
Repub=rand(patience,trials)<0.2;
for t=1:trials
    for i=1:patience
        if Repub(i,t)
            R(t)=i;
            break
        end
    end
end

n=1:max(R);
pR=histc(R,n)/trials;
P=(0.8.^(n-1))*0.2;
figure(1)
bar(n,pR,'r')
hold on
plot(n,P,'b')