1 #include<iostream>
 2 #include<string.h>
 3 using namespace std;
 4 
 5 double a[1005];
 6 
 7 int main(){
 8     int n1, n2;
 9     while(scanf("%d", &n1) != EOF){
10         memset(a, 0, sizeof(a));
11         for(int i = 1; i <= n1; i++){
12             int x;
13             double y;
14             scanf("%d%lf", &x, &y);
15             a[x] += y;
16         }
17         scanf("%d", &n2);
18         for(int i = 1; i <= n2; i++){
19             int x;
20             double y;
21             scanf("%d%lf", &x, &y);
22             a[x] += y;
23         }
24         int cnt = 0;
25         for(int i = 0; i <= 1000; i++){
26             if(a[i] != 0) cnt++; 
27         }
28         printf("%d", cnt);
29         for(int i = 1000; i >= 0; i--){
30             if(a[i] != 0){
31                 printf(" %d %.1lf", i, a[i]);
32             }
33         }
34         printf("\n");
35     }
36     return 0;
37 }