File I/O

# include <stdio.h>
int main( )
{
    FILE *filePointer,*fo ;
    int n;
    filePointer = fopen("input.txt", "r") ;
    fo=fopen("output.txt","w");
    if ( filePointer == NULL )
    {
        printf( "Failed to open \n" ) ;
    }
    else
    {
        printf("The file is now opened.\n") ;
        fscanf(filePointer,"%d",&n);
        int arr[n],i=0;
        fscanf(filePointer,"%d",&n);
        while(fscanf(filePointer,"%d",&arr[i])!=EOF){
            i++;
        }
        for(int i=0;i<n;i++){
            fprintf(fo,"%d ",arr[i]);
        }
        fclose(filePointer) ;
        fclose(fo);
        printf("The file is now closed.") ;
    }
    return 0;
}