C语言文件读写

重定向方式：

读：freopen("filenamein","r",stdin);

写：freopen("filenameout","w",stdout);

fopen方式：

读：File *fin;

fin = stdin;

fin = fopen("filenamein","rb");

fscanf(fin,"%d",&x);

fclose(fin);

写：File *fout;

fout = stdout;

fout = fopen("filenameout","wb");

fprintf(fout,"格式输出符",变量);

fclose(fout);