WATERRRRRRRRRRRRRRRRRRRRR

#include<bits/stdc++.h>
using namespace std; 
string a,b; 
double s; 
int cnt; 
int main(){
  cin>>a>>b; 
    for(int i=0;i<a.size();i++){
      if(a[i]==b[i]){ 
        cnt++; 
      } 
    }
  s=cnt*1.0/a.size();
  printf("%.2f",s);
  return 0; 
}