Submission #711346

#	Time	Username	Problem	Language	Result	Execution time	Memory
711346		PoonYaPat	Three Friends (BOI14_friends)	C++14	0 / 100	17 ms	5488 KiB

friends

#include <bits/stdc++.h>
using namespace std;

string s,ans;
int st,ed;

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    int n; cin>>n;
    cin>>s;

    if (s.size()%2==0) {
        cout<<"NOT POSSIBLE";
        return 0;
    }

    //consider insert letter in the middle
    bool ok=true;
    for (int i=0; i<s.size()/2; ++i) {
        if (s[i]!=s[i+s.size()/2+1]) ok=false;
    }
    if (ok) {
        for (int i=0; i<s.size()/2; ++i) ans+=s[i];
    }

    //consider insert letter on the left string
    for (int i=0; i<=s.size()/2; ++i) {
        if (s[i]!=s[i+s.size()/2+1] || i==s.size()/2) {
            ed=i;
            break;
        }
    }
    for (int i=s.size()/2; i>=0; --i) {
        if (s[i]!=s[i+s.size()/2] || i==0) {
            st=i;
            break;
        }
    }
    if (st<ed) {
        cout<<"NOT UNIQUE";
        return 0;
    } else if (st==ed) {
        if (ans.size()==0) {
            int k=0,idx=0;
            while (k<s.size()/2) {
                if (st!=idx) ans+=s[idx], ++k;
                ++idx;
            }
        } else {
            bool check=true;
            int k=0,idx=0;
            while (k<s.size()/2) {
                if (st!=idx){
                    if (ans[k]!=s[idx]) {
                        cout<<"NOT UNIQUE";
                        return 0;
                    } else ++k;
                }
                ++idx;
            }
        }
    }

    //consider insert letter on the right string
    for (int i=s.size()/2; i<s.size(); ++i) {
        if (s[i]!=s[i-s.size()/2] || i==s.size()-1) {
            ed=i;
            break;
        }
    }
    for (int i=s.size()-1; i>=s.size()/2; --i) {
        if (s[i]!=s[i-s.size()/2-1] || i==s.size()/2) {
            st=i;
            break;
        }
    }
    if (st<ed) {
        cout<<"NOT UNIQUE";
        return 0;
    } else if (st==ed) {
        if (ans.size()==0) {
            int k=0,idx=0;
            while (k<s.size()/2) {
                if (st!=idx) ans+=s[idx], ++k;
                ++idx;
            }
        } else {
            bool check=true;
            int k=0,idx=0;
            while (k<s.size()/2) {
                if (st!=idx){
                    if (ans[k]!=s[idx]) {
                        cout<<"NOT UNIQUE";
                        return 0;
                    } else ++k;
                }
                ++idx;
            }
        }
    }

    if (ans.size()==0) cout<<"NOT POSSIBLE";
    else cout<<ans;
}

Compilation message (stderr)

friends.cpp: In function 'int main()':
friends.cpp:19:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |     for (int i=0; i<s.size()/2; ++i) {
      |                   ~^~~~~~~~~~~
friends.cpp:23:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |         for (int i=0; i<s.size()/2; ++i) ans+=s[i];
      |                       ~^~~~~~~~~~~
friends.cpp:27:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |     for (int i=0; i<=s.size()/2; ++i) {
      |                   ~^~~~~~~~~~~~
friends.cpp:28:41: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |         if (s[i]!=s[i+s.size()/2+1] || i==s.size()/2) {
      |                                        ~^~~~~~~~~~~~
friends.cpp:45:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |             while (k<s.size()/2) {
      |                    ~^~~~~~~~~~~
friends.cpp:52:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |             while (k<s.size()/2) {
      |                    ~^~~~~~~~~~~
friends.cpp:50:18: warning: unused variable 'check' [-Wunused-variable]
   50 |             bool check=true;
      |                  ^~~~~
friends.cpp:65:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |     for (int i=s.size()/2; i<s.size(); ++i) {
      |                            ~^~~~~~~~~
friends.cpp:66:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |         if (s[i]!=s[i-s.size()/2] || i==s.size()-1) {
      |                                      ~^~~~~~~~~~~~
friends.cpp:71:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |     for (int i=s.size()-1; i>=s.size()/2; --i) {
      |                            ~^~~~~~~~~~~~
friends.cpp:72:41: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |         if (s[i]!=s[i-s.size()/2-1] || i==s.size()/2) {
      |                                        ~^~~~~~~~~~~~
friends.cpp:83:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |             while (k<s.size()/2) {
      |                    ~^~~~~~~~~~~
friends.cpp:90:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   90 |             while (k<s.size()/2) {
      |                    ~^~~~~~~~~~~
friends.cpp:88:18: warning: unused variable 'check' [-Wunused-variable]
   88 |             bool check=true;
      |                  ^~~~~

• Subtask 1: 0 / 35
• Subtask 2: 0 / 65