#include <stdio.h>
#include <stdlib.h>

#define tada media

typedef struct {
    int f;
    int p;
    int con;
    int cm;
} city;


double lercity(city v[], int n){
    int i, ct = 0;
    double tada = 0, pt = 0, inteiro, frac;
    for(i = 0; i < n; i++){
        scanf("%d %d", &v[i].p, &v[i].con);
        pt += v[i].p;
        ct += v[i].con;
        v[i].cm = (v[i].con)/(v[i].p);
        v[i].f = 1;
    }
    tada = (ct/pt);

        inteiro = (int)media;
        frac = media - inteiro;
        frac = frac*100;
        inteiro = inteiro*100;
        media = inteiro+(int)frac;
        media = media/100;

    return tada;

}

int cmp(const void* a, const void* b){
    city* p1 = (city*) a;
    city* p2 = (city*) b;

    if(p1->cm < p2->cm) return -1;
    else return 1;
    }

int main(){
    int n, i = 0, j;
    double tada;
    scanf("%d", &n);
    while(n){
        if(i != 0) printf("\n");
        i++;
        city v[n];
        tada = lercity(v, n);

        qsort(v, n, sizeof(city), cmp);

        for(j = 0; j < n-1; j++){

            if(v[j]. cm == v[j+1].cm){
                v[j].f = 0;
                v[j+1].p += v[j].p;
            }
        }

        printf("Cidade# %d:\n", i);
        if(v[0].f == 1)
        printf("%d-%d", v[0].p, v[0].cm);
        for(j = 1; j < n; j++){
            if(v[j]. f == 1)
            printf(" %d-%d", v[j].p, v[j].cm);
        }
        printf("\nConsumo medio: %.2lf m3.\n", tada);

        scanf("%d", &n);
    }
    return 0;
}