int main(int argc, char *argv[]){
int i;
FILE *fptr;
if((fptr=fopen("numb.txt","w"))==NULL) printf("\nCan't open file numb.txt\n"),exit(-1);
for (i=0;i<1000000;++i)
{
int k=i;
int j;
for (j=100000;j>0;j=j/10)
{
fputc('0'+(k/j)%10,fptr);
}
if (i<999999) fputc('\n',fptr);
}
fclose(fptr);
}