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

#define N 12

int main(){
int s,i,j,l,m,n,k,mes[];
float temp[],temp_med[];

FILE*df_in,*df_out;

df_in=fopen("temperaturas.txt","r");
df_out=fopen("temp_med.txt","w");
if(df_in==NULL || df_out==NULL){
printf("error abriendo el fichero");
system ("PAUSE");
return -1;
}
i=1;
s=0;
while(fscanf(df_in,"%d%f",&mes[l],&temp[m])!=EOF{
if(mes[l]==i){
s+=temp[m];
j++}
if(mes[l]>i){
temp_med[n]=s/j;
j=0;
i++;
n++;}
l++;
m++;
}
for(k=1;k<=12;k++)
fprintf(df_out,"%d%f\n",k,temp_med[k]);
fclose(df_in,df_out);
system ("PAUSE");
return 0;
}