Reading numbers from a text file into an array in C
I'm a programming noob so please bear with me.
I'm trying to read numbers from a text file into an array. The text file, "somenumbers.txt" simply holds 16 numbers as so "5623125698541159".
#include <stdio.h>
main()
{
FILE *myFile;
myFile = fopen("somenumbers.txt", "r");
//read file into array
int numberArray[16];
int i;
for (i = 0; i < 16; i++)
{
fscanf(myFile, "%d", &numberArray[i]);
}
for (i = 0; i < 16; i++)
{
printf("Number is: %d\n\n", numberArray[i]);
}
}
The program doesn't work. It compiles but outputs:
Number is: -104204697
Number is: 0
Number is: 4200704
Number is: 2686672
Number is: 2686728
Number is: 2686916
Number is: 2004716757
Number is: 1321049414
Number is: -2
Number is: 2004619618
Number is: 2004966340
Number is: 4200704
Number is: 2686868
Number is: 4200798
Number is: 4200704
Number is: 8727656
Process returned 20 (0x14) execution time : 0.118 s Press any key to continue.
change to
fscanf(myFile, "%1d", &numberArray[i]);
5623125698541159
is treated as a single number (out of range of int
on most architecture). You need to write numbers in your file as
5 6 2 3 1 2 5 6 9 8 5 4 1 1 5 9
for 16 numbers.
If your file has input
5,6,2,3,1,2,5,6,9,8,5,4,1,1,5,9
then change %d
specifier in your fscanf
to %d,
.
fscanf(myFile, "%d,", &numberArray[i] );
Here is your full code after few modifications:
#include <stdio.h>
#include <stdlib.h>
int main(){
FILE *myFile;
myFile = fopen("somenumbers.txt", "r");
//read file into array
int numberArray[16];
int i;
if (myFile == NULL){
printf("Error Reading File\n");
exit (0);
}
for (i = 0; i < 16; i++){
fscanf(myFile, "%d,", &numberArray[i] );
}
for (i = 0; i < 16; i++){
printf("Number is: %d\n\n", numberArray[i]);
}
fclose(myFile);
return 0;
}
for (i = 0; i < 16; i++)
{
fscanf(myFile, "%d", &numberArray[i]);
}
This is attempting to read the whole string, "5623125698541159"
into &numArray[0]
. You need spaces between the numbers:
5 6 2 3 ...