Submission #861380

#	Time	Username	Problem	Language	Result	Execution time	Memory
861380		imarn	Combo (IOI18_combo)	C++14	Compilation error	0 ms	0 KiB

combo

int press(std::string p);
std::string guess_sequence(int N){
    std::string ans="";
    char s[4];
    if(press("A")==1)ans="A",s[0]='A',s[1]='B',s[2]='X',s[3]='Y';
    else if(press("B")==1)ans="B",s[0]='B',s[1]='A',s[2]='X',s[3]='Y';
    else if(press("X")==1)ans="X",s[0]='X',s[1]='B',s[2]='A',s[3]='Y';
    else ans="Y",s[0]='Y',s[1]='B',s[2]='X',s[3]='A';
    for(int i=2;i<=N-1;i++){
        std::string now1 = ans;now1+=s[1];
        std::string now2 = ans;now2+=s[2];now2+=s[1];
        std::string now3 = ans;now3+=s[2];now3+=s[2];
        std::string now4 = ans;now4+=s[2];now4+=s[3];
        std::string tt = now1+now2+now3+now4;
        int x = press(tt);
        if(x==i-1)ans = ans+s[3];
        else if(x==i)ans = ans+s[1];
        else ans = ans+s[2];
    }
    string tt1=ans;tt1+=s[1];
    string tt2=ans;tt2+=s[2];
  	if(press(tt1)==N){
        return tt1;
    }
    else if(press(tt2)==N){
        return tt2;
    }
    else{
        ans+=s[3];return ans;
    }
}

Compilation message (stderr)

combo.cpp:1:16: error: 'string' is not a member of 'std'
    1 | int press(std::string p);
      |                ^~~~~~
combo.cpp:1:1: note: 'std::string' is defined in header '<string>'; did you forget to '#include <string>'?
  +++ |+#include <string>
    1 | int press(std::string p);
combo.cpp:2:6: error: 'string' in namespace 'std' does not name a type
    2 | std::string guess_sequence(int N){
      |      ^~~~~~
combo.cpp:2:1: note: 'std::string' is defined in header '<string>'; did you forget to '#include <string>'?
    2 | std::string guess_sequence(int N){
      | ^~~