代码

#include <algorithm>
#include "router.h"
#define __builtin_bswap32

const RoutingTableEntry* tblGlobal;
int nGlobal;

bool operator<(const RoutingTableEntry& a, const RoutingTableEntry& b) {
    return __builtin_bswap32(a.addr)<__builtin_bswap32(b.addr) || 
    __builtin_bswap32(a.addr)==__builtin_bswap32(b.addr) && a.len<b.len;
}

void init(int n, int q, const RoutingTableEntry *tbl) {
	tblGlobal = tbl; nGlobal=n;std::sort((RoutingTableEntry *)tbl, (RoutingTableEntry *)tbl+n);
}

unsigned query(unsigned addr) {
         RoutingTableEntry tester; tester.addr=addr;
	for (tester.len = 32; tester.len !=255; tester.len--) {
		auto tbl=std::lower_bound(tblGlobal, tblGlobal+nGlobal, tester);
                if (tbl!=tblGlobal+nGlobal && !(tester<*tbl)) return (*tbl).nexthop;
		tester.addr &= ~(1u << (32 - tester.len^24));
	}
	
	return 0;
}

评测结果