Why am I getting these seemingly random output? - c

Question

I am stuck at a C language problem in which I was supposed to input name and age of players from their respective files and output the same for a specific number of players which will be taken input (OR -1 to exit). The problem has to be solved using structures. I have attached the output I am getting along with the data that the age and name files contained.
Can someone explain to me where I am doing wrong?
Any help in optimisation too will be really helpful. Thanks!
Following is the code
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Cricket_Player_DataBase
{
char name[30];
int score;
char role[11];
int age;
int wickets;
};
int main()
{
FILE *nf_ptr , *af_ptr; //nf_ptr is pointing to name.txt file | af_ptr is pointing to age.txt file
nf_ptr = fopen("name.txt","r");
af_ptr = fopen("age.txt","r");
int number_of_players = 0; //will be used to fix the size of array of structures
// following code is used just to count number of players, upto the point where 'HERE' is written
int temp, border_check = 0;
while((temp = fgetc(af_ptr)) != EOF)
{
if(temp == '\n')
{
++number_of_players;
border_check = 0;
}
else border_check++;
}
if(border_check > 0) ++number_of_players;
af_ptr = fopen("age.txt","r");
// HERE
struct Cricket_Player_DataBase players[number_of_players];
int temp_age , zero = 0 ;
char temp_char[30] , ch ;
for(int i=0; i < number_of_players; ++i)
{
temp_age = fgetc(af_ptr);
players[i].age = temp_age;
while((ch = fgetc(nf_ptr)) != EOF)
{
if(ch == '\n')
{
strncpy(players[i].name , temp_char , zero+1);
zero = 0;
break;
}
else
{
temp_char[zero] = ch;
zero++;
}
}
}
int input;
printf("Enter number of players you want to see the data of OR type -1 to exit : ");
scanf("%d", &input);
if(input > 0)
{
for(int i = 0; i < input; ++i)
{
printf("Data of player #%d is \nName : %s\nAge : %d\n", i+1 , players[i].name , players[i].age);
}
}
fclose(nf_ptr);
fclose(af_ptr);
return 0;
}
Output I got.
Name file was this.
Age file was this.

Answer 1

You're opening af_ptr without closing it. It could cause problems. If you want to open the same file again, use function rewind(file) or fclose it and open it again.

Answer 2

This is because you have made an assumption that the end of each name and age in your text files is a line feed character '\n'. Assuming you have created your text files in a windows machine, the line endings are \r\n, that is - a carriage return character followed by a line feed. Using Hex Editor Neo, here's what your files' contents would look like.
Your name.txt file
Your age.txt file
Notice the line endings - '0x0d' is a carriage return '\r' and '0x0a' is a line feed '\n'. Modify your program to take this into account.
Read more about line endings here: https://blog.codinghorror.com/the-great-newline-schism/