#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int n,a,b,c,d,x=1,i; cin>>n; cin>>a>>b>>c>>d; if(b-a==c-b){ for(i=a;x<=n-1;x++){ i+=b-a; } cout<<i; } else if(b/a==c/b){ for(i=a;x<=n-1;x++){ i*=b/a; } cout<<i; } return 0; }