Submission #1215066

#	Time	Username	Problem	Language	Result	Execution time	Memory
1215066		LM1	Combo (IOI18_combo)	C++20	Compilation error	0 ms	0 KiB

combo

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define ff first
#define ss second
#define pb push_back
#define vi vector<int>
#define fr(i,ii,iii) for(int i=ii;i<iii;i++)
#include "combo.h"
string guess_sequence(int N){
	string ans="";
	int x;
	x=press("AB");
	if(x==2)ans="A";
	else if(x==1){
		x=press("A");
		if(x==1){
			ans="A";
		}
		else ans="B";
	}
	else{
		x=press("X");
		if(x==1){
			ans="X";
		}
		else ans="Y";
	}
	string a;
	vector<char>v={'A','B','C','D'};
	fr(i,0,4){
		if(v[i]==ans[0]){
			v.erase(v.begin()+i);
			break;
		}
	}
	fr(i,2,n){
		a=ans;
		a+=v[0];
		a+=ans;
		a+=v[1];a+=v[0];
		a+=v[1];a+=v[1];
		a+=v[1];a+=v[2];
		x=press(a);
		if(x==ans.size()){
			ans+=v[2];
			continue;
		}
		if(x==ans.size()+1){
			ans+=v[0];
			continue;
		}
		if(x==ans.size()+2){
			ans+=v[1];
			continue;
		}
	}
	a=ans;
	a+=v[0];
	x=press(a);
	if(x==ans.size()+1){
		return a;
	}
	else{
		a=ans;
		a+=v[1];
		x=press(a);
		if(x==ans.size()+1){
			return a;
		}
		else{
			ans+=v[2];
			return ans;
		}
	}
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:38:16: error: 'n' was not declared in this scope
   38 |         fr(i,2,n){
      |                ^
combo.cpp:9:37: note: in definition of macro 'fr'
    9 | #define fr(i,ii,iii) for(int i=ii;i<iii;i++)
      |                                     ^~~