浮点精度

#include <cstdio>
#include <cmath>
#define AC 0
#define WA 1
const double eps = 1e-3;
int main(int argc, char *args[]) {
    FILE *f_in = fopen(args[1], "r");
    FILE *f_user = fopen(args[2], "r");
    FILE *f_out = fopen(args[3], "r");
    int ret = AC;
    int t;
    double a, x;
    fscanf(f_in, "%d", &t);
    while (t--) { //从输入中读取数据组数 t
        fscanf(f_out, "%lf", &a);
        fscanf(f_user, "%lf", &x);
        if (fabs(a - x) > eps) {
            ret = WA; // Wrong Answer
            break;
        }
    }

    fclose(f_in);
    fclose(f_out);
    fclose(f_user);
    return ret;
}

多种解

#include <cstdio>
#include <cstring>

#define AC 0
#define WA 1


const int N=510;

int h[N],e[N],ne[N],idx;
int d[N];  // 入度
int a[N];
int n;

void add (int a, int b) {
    e[idx] = b, ne[idx] = h[a], h[a] = idx ++ ;
}

bool judge() {
    for(int j=1; j<=n; j++) {
        int id=a[j];
        if(d[id]!=0) {
            return false;
        }   
        for(int i=h[id]; i!=-1; i=ne[i]) {
            int u=e[i];
            d[u]--;
        }
    }
    return true;
}

int main(int argc,char *args[]) {
    memset (h,-1,sizeof h);
    FILE * f_in = fopen(args[1],"r");//标准输入
    FILE * f_user = fopen(args[2],"r");//用户输出
    FILE * f_out = fopen(args[3],"r");//标准输出
    int ret = AC;

    fscanf(f_in, "%d", &n);
    for (int i = 1; i <= n; i ++ ) {
        int son;
        while(fscanf(f_in, "%d", &son)==1 ,son) {
            add(i, son);
            d[son] ++ ;
        }
    }

    for (int i = 1; i <= n; i ++ ) {
        fscanf(f_user, "%d", &a[i]);
    }

    if(!judge()) {
        ret = WA;
    }

    fclose(f_in);
    fclose(f_out);
    fclose(f_user);
    return ret;
}

注意：必须要在本地编译器编译通过！

—— 本文来自火龙信奥（义乌睿码科技）：义乌青少年信息学奥赛与编程教育平台，专注 CSP-J/S、NOIP、GESP 竞赛培训，线上线下融合教学，助力编程升学。网址：hlcoding.com