文件操作（重定向与不含重定向）

重定向版

#include<iostream>
#include<cstdio>

using namespace std;

int main()
{
    freopen("F:\\in.txt","r",stdin);
    freopen("F:\\out.txt","w",stdout);
    int s;
    scanf("%d",&s);
    printf("%d\n",s);
    return 0;
}

标准版

#include<iostream>
#include<cstdio>

using namespace std;

int main()
{
    FILE *fin,*fout;
    fin=fopen("F:\\in.txt","rb");
    fout=fopen("F:\\out.txt","wb");
    int x;
    fscanf(fin,"%d",&x);
    int s=x;
    fprintf(fout,"%d\n",s);
    fclose(fin);
    fclose(fout);
    return 0;
}