代码

#include "router.h"
#include <cstdio>
#include <arpa/inet.h>

int n;
const RoutingTableEntry *a;

void init(int _n, int _q, const RoutingTableEntry *_a)
{
    n = _n, a = (RoutingTableEntry *)_a;
}

unsigned query(unsigned addr)
{
    addr = htonl(addr);
    unsigned table_addr = 0;
    unsigned nexthop = 0;
    int len = -1;
    // for (int i = n; i--;)
    for (int i = 0; i < n; ++i)
        if (a[i].len == 0 && len == -1)
            nexthop = a[i].nexthop, len = 0;
        else if ((len == -1 || a[i].len > len) && ((addr ^ htonl(a[i].addr)) & -(1 << 32 - a[i].len)) == 0)
        {
            nexthop = a[i].nexthop, len = a[i].len;
            table_addr = htonl(a[i].addr);
        }
    // printip("table_addr", table_addr);
    // printf("len = %d\n", len);
    return nexthop;
}

评测结果