銆愰殢鏈恒€戞鐜囧垎鏋愨€斺€攃f1364E

Posted 2020-12-10

鏍囩锛?a href='http://www.mamicode.com/so/1/%e7%94%b5%e8%84%91' title='鐢佃剳'>鐢佃剳   int   lock   涓暟   epo   namespace   and   random   骞朵笖   

缁欏畾涓€涓猍0,n-1]鎺掑垪p锛屾瘡娆¤闂?i,j)杩斿洖pi|pj,鏈€澶?269娆¤闂紝鎺ㄥ嚭杩欎釜鎺掑垪

鏈鍏抽敭鍦ㄤ簬纭畾0鐨勪綅缃?/p>

涓€涓粨璁猴細鎴戜滑鍙互閫氳繃涓ゆ璇㈤棶锛屼粠涓変釜鏁颁腑鎺掗櫎鎺変竴涓偗瀹氫笉鏄?鐨勬暟

鍥犳锛氭垜浠淮鎶や綇涓や釜鍊间笅鏍嘺,b,骞朵笖鍋囪0鍦╬a,pb杩欎袱涓暟涓嚭鐜?/p>

鍒濆鏃禷=0,b=1,鐒跺悗鏋氫妇c=[2..n-1]

銆€銆€pa|pc > pb|pc : 閭ｄ箞pa蹇呯劧涓嶆槸0锛屾垜浠妸a鎹㈡垚c

銆€銆€pa|pc < pb|pc锛氶偅涔坧b蹇呯劧涓嶆槸0锛屾垜浠妸b鎹㈡垚c

銆€銆€pa|pc = pb|pc锛氶偅涔坧c蹇呯劧涓嶆槸0锛屼笉鐢ㄦ崲

鏋氫妇瀹屽悗鎴戜滑鍙互纭畾0蹇呭畾鍦╬a,鎴杙b涓や釜鏁颁腑鍑虹幇锛岃€岃纭畾绌剁珶鍦ㄥ摢涓綅缃紝鎴戜滑鍙渶瑕侀殢鏈洪€夊叾浠栦换浣曚竴涓綅缃畑锛?/p>

銆€銆€濡傛灉pa|px != pb|px,灏卞彲浠ョ‘瀹?鐨勪綅缃簡锛岃繖涓楠ら噸澶嶄釜鍑犳(棰樼洰鐨勮寖鍥村厑璁?00+娆?灏卞彲浠?/p>

纭畾0鐨勪綅缃悗锛屽叾浠栨暟璇㈤棶璧锋潵灏卞緢绠€鍗曚簡

 

ps:鎴戠殑鐢佃剳濂藉儚涓嶈兘鍐檙andom浜嗐€傘€傝糠鎯戙€傘€?/p>

鎼繍涓嬮瑙ｏ紝浠ュ悗鍐嶅啓涓€娆?/p>

#include <bits/stdc++.h>
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int p[(1<<11)+5];
int query(int i,int j)
{
    printf("? %d %d
",i,j);
    fflush(stdout);
    int ans;
    scanf("%d",&ans);
    assert(ans!=-1);
    return ans;
}
int main()
{
    int n;
    scanf("%d",&n);
    vector<int> qp;
    for (int i=1;i<=n;i++)
    qp.push_back(i);
    int a=qp[0],b=qp[1],val=query(a,b);
    for (int i=2;i<n;i++)
    {
        int tmp=query(b,qp[i]);
        if (tmp<val)
        {
            a=qp[i];
            val=tmp;
        }
        else if (tmp==val)
        {
            b=qp[i];
            val=query(a,qp[i]);
        }
    }
    int idx;
    while (1)
    {
        int i=uniform_int_distribution<int>(1,n)(rng);
        if (i==a || i==b)
        continue;
        int t1=query(i,a),t2=query(i,b);
        if (t1!=t2)
        {
            idx=(t1<t2? a:b);
            break;
        }
    }
    for (int i=1;i<=n;i++)
    {
        if (i!=idx)
        p[i]=query(i,idx);
    }
    printf("!");
    for (int i=1;i<=n;i++)
    printf(" %d",p[i]);
    printf("
");
    fflush(stdout);
}