#include<iostream> #include<cstdio> //scanf()\printf() #include<cstring> #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int j=0,y=0,sum=0; for(int i=1;i<=1000;i++){ j++; y++; if(j==21) j=1; if(y==31) y=1; if(j==y) sum+=1; } cout<<sum; return 0; }