How to print lines from a file in reverse order

c

I am trying to print a file in reverse order. I am using arrays to save each lines data. So far I was able to print every line in a normal order.

index is the number of lines I am referring to and FuncIndex the same thing but has been declared again in the function.

file = fopen("../quotes.data","r");
while (NumOfField == 8) {
    NumOfField = fscanf(file,"%d,%c,%d,%d,%c,%c,%lf,%lf", &quote[index], &roomletter[index], &length[index], &width[index], &paint[index], &ceiling[index], &cost[index], &setup_cost[index]);
    index++;
}
index--;
fclose(file);

In Function: 

int FuncIndex;
for (FuncIndex = 0; FuncIndex <= index; FuncIndex++) {
    printf("\n%5d   %1c   %3d    %3d    %1c      %1c    %8.2lf %6.2lf", quote[FuncIndex], roomletter[FuncIndex], length[FuncIndex], width[FuncIndex], paint[FuncIndex], ceiling[FuncIndex], cost[FuncIndex], setup_cost[FuncIndex]);
}

Now I tried changing the for loop to:

for (FuncIndex = index; FuncIndex >= 0; FuncIndex--) >

But the output prints empty. Although when I change the 0 to any number, that corresponding line gets printed.

The output That prints is:

Quote Room Length Width Paint Ceiling     Cost  Setup
===== ==== ====== ===== ===== =======  =======  =====
531   A    10     10    b      n       96.00 100.00
531   B    15     15    b      n      144.00   0.00
531   C    20     20    b      n      192.00   0.00

I am looking to get this output reversed like:

Quote Room Length Width Paint Ceiling     Cost  Setup
===== ==== ====== ===== ===== =======  =======  =====
531   C    20     20    b      n      192.00   0.00
531   B    15     15    b      n      144.00   0.00
531   A    10     10    b      n       96.00 100.00

Please excuse me if I putted the output in the code section because then the formatting would change

Thank you.

Best Answer

Maybe you should post all your code (however, try to reduce it to minimum). This works for me:

File input.txt

530 A
531 B
532 C

#include <stdio.h>
#include <conio.h>

#define MAX_LINES 50

int main()
{
    FILE* file;
    int NumOfField = 2;
    int index = 0;
    char roomLetter[ MAX_LINES ];
    int  quote     [ MAX_LINES ];

    file = fopen("input.txt","r");

    while ( NumOfField == 2 ) {
        NumOfField = fscanf(file,"%d %c\n", &quote[index], &roomLetter[index]);
        index++;
    }
    fclose(file);
    index--;

    for(; index >=0; index-- )
        printf( "%d %c\n", quote[index], roomLetter[index] );

    getch();

    return 0;
}
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