Submission #170671

#	Time	Username	Problem	Language	Result	Execution time	Memory
170671		liwi	Combo (IOI18_combo)	C++11	5 / 100	3 ms	256 KiB

combo

#include "combo.h"

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
typedef gp_hash_table<int, null_type,hash<int>, equal_to<int>, direct_mask_range_hashing<int>, linear_probe_fn<>,
    hash_standard_resize_policy<hash_exponential_size_policy<>, hash_load_check_resize_trigger<true>,true>> hash_set;

#define scan(x) do{while((x=getchar())<'0'); for(x-='0'; '0'<=(_=getchar()); x=(x<<3)+(x<<1)+_-'0');}while(0)
char _;
#define complete_unique(a) a.erase(unique(a.begin(),a.end()),a.end())
#define all(a) a.begin(),a.end()
#define println printf("\n");
#define readln(x) getline(cin,x);
#define pb push_back
#define endl "\n"
#define INT_INF 0x3f3f3f3f
#define LL_INF 0x3f3f3f3f3f3f3f3f
#define EPS 1e-9
#define MOD 1000000007
#define MOD2 1494318097
#define SEED 131
#define mp make_pair
#define fastio cin.tie(0); cin.sync_with_stdio(0);

typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef pair<int,pii> triple;
typedef int8_t byte;

mt19937 g1(chrono::steady_clock::now().time_since_epoch().count());

int randint(int a, int b){return uniform_int_distribution<int>(a, b)(g1);}
ll randlong(ll a,ll b){return uniform_int_distribution<long long>(a, b)(g1);}

ll gcd(ll a, ll b){return b == 0 ? a : gcd(b, a % b);}
ll lcm(ll a, ll b){return a*b/gcd(a,b);}
ll fpow(ll  b, ll exp, ll mod){if(exp == 0) return 1;ll t = fpow(b,exp/2,mod);if(exp&1) return t*t%mod*b%mod;return t*t%mod;}
ll divmod(ll i, ll j, ll mod){i%=mod,j%=mod;return i*fpow(j,mod-2,mod)%mod;}

vector<char> v = {'A','B','X','Y'};

string guess_sequence(int len){
    string ret = "";
    for(int i=0; i<3; i++){
        int a = press(string(1,v[i]));
        if(a == 1){
            ret = string(1,v[i]);
            break;
        }
    }
    if(ret.empty()) ret = v.back();
    v.erase(find(all(v),ret[0]));
    for(int i=2; i<len; i++){
        int a = press(ret+v[0]+ret+v[1]+v[0]+ret+v[1]+v[1]+ret+v[1]+v[2]);
        if(a == i-1) ret+=v[2];
        else if(a == i) ret+=v[0];
        else ret+=v[1];
    }
    for(int i=0; i<2; i++){
        int a = press(ret+v[i]);
        if(a == len){
            ret+=v[i];
            break;
        }
    }
    if(ret.size() != len) ret+=v.back();
    return ret;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:75:19: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   75 |     if(ret.size() != len) ret+=v.back();
      |        ~~~~~~~~~~~^~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 95