#include<stdio.h>
int main(){
FILE *fp = fopen("D:\\C++---C++17first\\C---advance\\test1.txt", "r");
if(fp){
int num;
fscanf(fp,"%d",&num);
printf("%d\n",num);
fclose(fp);
}else{
printf("无法打开文件\n");
}
return 0;
}