bool s1(float &average){
    bool result = true;

    char filename[80];
    printf("Enter your filename: ");
    scanf("%s", &filename);

    FILE *file = fopen(filename, "r");
    if(file == NULL)
       result = false;
    else{
       float current = 0.0f, s = 0.0f;
       int count = 0;
       while(!feof(file)){
          if(fscanf(file, "%f", &current)){
              s = sum(s, current);
              ++count;
          }
       }
       if(count == 0)
          result = false;
       else
          average = s / (1.0f * count);
    }
    fclose(file);

    return result;
}
float sum(float &s, float &current){
    return (s + current);
}