Submission #677494

#	Time	Username	Problem	Language	Result	Execution time	Memory
677494		hello_there_123	Combo (IOI18_combo)	C++17	Compilation error	0 ms	0 KiB

combo

#include<bits/stdc++.h>
//#include "combo.h"
using namespace std;
string arr[4]={"A","B","X","Y"};
set<string>st;
int press(string s);
string guess_sequence(int N){
  	if(N==1){
		for(int i=0;i<4;i++){
			if(press(arr[i]) == 1) return arr[i];
        }
    }
	string ans = "";
	string start = "";
	st.insert("A");
	st.insert("B");
	st.insert("X");
	st.insert("Y");
  	for(int i=0;i<4;i++){
		string tr = "";
      	for(int j=0;j<4;j++){
        	tr = tr+arr[i]+arr[j];
		}		
      if(press(tr) == 2){
      	start = arr[i];
        break;
      }
      }
    }
	if(start == "") start = "Y";
	st.erase(start);
	vector<string>v;
	for(auto string:st) v.push_back(string);
	ans+=start;
  	assert(ans.length() == 1);
	for(int i=0;i<N-2;i++){
		string tr = "";
		tr+=ans;
		tr+=v[0];
		tr+=ans;
		tr+=v[1];
		tr+=v[0];
		tr+=ans;
		tr+=v[1];
		tr+=v[1];
		tr+=ans;
		tr+=v[1];
		tr+=v[2];
		if(press(tr) == ans.length()){
			ans+=v[2];
		}
		else if(press(tr) == ans.length()+1){
			ans+=v[0];
		}
		else ans+=v[1];
		
	}
	if(press(ans+v[0]) == N) return ans+v[0];
	if(press(ans+v[1]) == N) return ans+v[1];
	if(press(ans+v[2])==N) return ans+v[2];
  	assert(1);
 
}

Compilation message (stderr)

combo.cpp:30:2: error: expected unqualified-id before 'if'
   30 |  if(start == "") start = "Y";
      |  ^~
combo.cpp:31:2: error: 'st' does not name a type
   31 |  st.erase(start);
      |  ^~
combo.cpp:33:2: error: expected unqualified-id before 'for'
   33 |  for(auto string:st) v.push_back(string);
      |  ^~~
combo.cpp:34:2: error: 'ans' does not name a type; did you mean 'abs'?
   34 |  ans+=start;
      |  ^~~
      |  abs
In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from combo.cpp:1:
combo.cpp:35:4: error: expected unqualified-id before 'static_cast'
   35 |    assert(ans.length() == 1);
      |    ^~~~~~
combo.cpp:35:4: error: expected ')' before 'static_cast'
combo.cpp:36:2: error: expected unqualified-id before 'for'
   36 |  for(int i=0;i<N-2;i++){
      |  ^~~
combo.cpp:36:14: error: 'i' does not name a type
   36 |  for(int i=0;i<N-2;i++){
      |              ^
combo.cpp:36:20: error: 'i' does not name a type
   36 |  for(int i=0;i<N-2;i++){
      |                    ^
combo.cpp:58:2: error: expected unqualified-id before 'if'
   58 |  if(press(ans+v[0]) == N) return ans+v[0];
      |  ^~
combo.cpp:59:2: error: expected unqualified-id before 'if'
   59 |  if(press(ans+v[1]) == N) return ans+v[1];
      |  ^~
combo.cpp:60:2: error: expected unqualified-id before 'if'
   60 |  if(press(ans+v[2])==N) return ans+v[2];
      |  ^~
In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from combo.cpp:1:
combo.cpp:61:4: error: expected unqualified-id before 'static_cast'
   61 |    assert(1);
      |    ^~~~~~
combo.cpp:61:4: error: expected ')' before 'static_cast'
combo.cpp:63:1: error: expected declaration before '}' token
   63 | }
      | ^
combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:13:15: warning: control reaches end of non-void function [-Wreturn-type]
   13 |  string ans = "";
      |               ^~