#include <iostream> using namespace std; int m; int equal_difference(int n) { int r; if(n==1){ r=1; } else{ r=equal_difference(n-1)+m; } return r; } int ratio_of_equality(int n){ int r; if(n==1){ r=1; } else{ r=ratio_of_equality(n-1)*m; } return r; } int main() { int a[101],n; cin>>n; for(int i=1;i<=4;i++) { cin>>a[i]; } if(a[2]-a[1]==a[3]-a[2]&&a[3]-a[2]==a[4]-a[3]&&a[2]-a[1]==a[4]-a[3]) { m=a[2]-a[1]; cout<<equal_difference(n); } else { m=a[2]/a[1]; cout<<ratio_of_equality(n); } }