//生成N个小于N的随机数，存入数组a
void RandToFile(int *a)
{
srand( (unsigned)time( NULL ) ); //初始化随机数
for(int i=0;i<N;i++)
{
a[i]=(int)rand()%N;
}
FILE *fp;
if((fp=fopen("data.txt","w"))==NULL)
{
printf("\nerror on open data.txt!");
getch();
exit(1);
}
for(i=0;i<N;i++)
fprintf(fp,"%1d\n",a[i]);
fclose(fp);
}

数据写入文件