#include<bits/stdc++.h>
using namespace std;
int main(){
    double a,b,c,d,e,f,g,h,i,j,m,n,sum=0;
    cin>>a>>b>>c>>d>>e>>f>>g>>h>>i>>j>>m>>n;
      sum=a+b+c+d+e+f+g+h+i+j+m+n;
    printf("%.2lf",sum/12);
}

#include<bits/stdc++.h> using namespace std; double a[101]; int main(){ double sum=0;

for(int i=1;i<=12;i++){
	cin>>a[i];
	
	sum=sum+a[i];
}

printf("%.2lf",sum/12);

} //不是一个for循环都写不明白吗

#include<bits/stdc++.h>
using namespace std;
int main(){
    double a,b,c,d,e,f,g,h,i,j,m,n,sum=0;
    cin>>a>>b>>c>>d>>e>>f>>g>>h>>i>>j>>m>>n;
      sum=a+b+c+d+e+f+g+h+i+j+m+n;
    printf("%.2lf",sum/12);
}

#include<bits/stdc++.h> using namespace std; int main(){ double a; double sum = 0;

for(int i = 1;i<=12;i++){
	cin>>a;
	sum=sum+a;
}
double b;
b=sum/12;
printf("%.2lf",b);
return 0;

}

#include<bits/stdc++.h> using namespace std; int main(){ int b; b=12; double a,sum=0.00,d=0.00,i; for(i=1.00;i<=b;i++){ cin>>d; sum+=d; } a=1.0*sum/b; printf("%.2lf",a); return 0; } 没人用循环吗

#include<bits/stdc++.h> using namespace std; int main(){ double a,b,c,d,e,f,g,h,i,j,m,n,sum=0; cin>>a>>b>>c>>d>>e>>f>>g>>h>>i>>j>>m>>n; sum=a+b+c+d+e+f+g+h+i+j+m+n; printf("%.2lf",sum/12); }

#include<bits/stdc++.h> using namespace std; int main(){ double a,b,c,d,e,f,g,h,i,j,m,n,sum=0; cin>>a>>b>>c>>d>>e>>f>>g>>h>>i>>j>>m>>n; sum=a+b+c+d+e+f+g+h+i+j+m+n; printf("%.2lf",sum/12); }

#include<bits/stdc++.h>
using namespace std;
int main(){
    double a,b,c,d,e,f,g,h,i,j,m,n,sum=0;
    cin>>a>>b>>c>>d>>e>>f>>g>>h>>i>>j>>m>>n;
      sum=a+b+c+d+e+f+g+h+i+j+m+n;
    printf("%.2lf",sum/12);
}

#include<bits/stdc++.h> using namespace std; int main(){ double d=12,b,sum=0,i; for(i=1;i<=d;i++){ cin>>b; sum+=b; } printf("%.2lf",sum/d); return 0; }

#include<bits/stdc++.h> using namespace std; int main() { double a=0,c,sum=0; double z; while(a<12){ cin>>c; sum=sum+c; a++; } z=sum*1.0/12; printf("%.2lf",z); return 0; }

#include<bits/stdc++.h> using namespace std; int main(){ float a,b,c,d,e,f,g,h,i,j,k,l,m,nsum=0; cin>>a; cin>>b; cin>>c; cin>>d; cin>>e; cin>>f; cin>>g; cin>>h; cin>>i; cin>>j; cin>>k; cin>>l; m=1.0*(a+b+c+d+e+f+g+h+i+j+k+l)/12; printf("%.2lf",m); return 0; }

#include<iostream>
using namespace std;
int main(){
    float q,w,e,r,t,y,u,i,o,p,a,s,d;
    cin>>q;cin>>w;
    cin>>e;
    cin>>r;
    cin>>t;
    cin>>y;
    cin>>u;
    cin>>i;
    cin>>o;
    cin>>p;
    cin>>a;
    cin>>s;
    d= (q+w+e+r+t+y+u+i+o+p+a+s)/12;
	printf("%.2lf", d);
	return 0;
}

1+1=2