#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cstdlib> #include<ctime> #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; /*void a(int x){ if(x>100){ return; } cout<<x++<<endl; a(x); } int main(){ int x=1; a(x); return 0; } void a(int x){ if(x>=18){ return; }x+=2; cout<<x<<endl; a(x); } int main(){ int x=8; a(x); return 0; } void c(int b){ for(int i=9;i>0;i--){ b=2*(b+1); } cout<<b; } int main(){ int b=1; c(b); return 0; }*/ int main() { unsigned int n; unsigned long long factorial = 1; cin >> n; for(int i = 1; i <=n; ++i) { factorial *= i; } cout << factorial; return 0; }