#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int m; cin>>m; cout<<m+10-30+20-5; return 0; }