# include<iostream> # include<cstdio> # include<iomanip> # include<cmath> using namespace std; int main(){ int n=0,x=0,sum=0,i=0; while(sum<=1000) { n++; if(n>20) n=1; x++; if(x>30) x=1; sum++; if(n==x) i++; } cout<<i; return 0; }