Submission #748432

#	Time	Username	Problem	Language	Result	Execution time	Memory
748432		mariowong	Three Friends (BOI14_friends)	C++14	0 / 100	1 ms	468 KiB

friends

#include <bits/stdc++.h>
using namespace std;
 
int n,pos1,pos2,ct,ans;
string s,t,r,anss;
bool ok;
int main(){
	ios::sync_with_stdio(false);
  	scanf("%d%s",&n,s);
	if (n%2 == 0){
		cout << "NOT POSSIBLE\n";
		return 0;
	}
	for (int i=1;i<=n/2;i++){
		t+=s[i];
	}
	for (int i=n/2+1;i<n;i++){
		r+=s[i];
	}
	for (int i=0;i<n/2;i++){
		if (t[i] == r[i])
		ct++;
	}
	for (int i=0;i<n;i++){
		if (ct == n/2){
			ans++;
			if (ans > 1 && t != anss)
			ok=true;
			else
			if (ans == 1)
			anss=t;
		}
		if (pos1 != n/2){
			if (t[pos1] == r[pos1])
			ct--;
			t[pos1]=s[i];
			if (t[pos1] == r[pos1])
			ct++;
			pos1++;
		}
		else
		{
			if (t[pos2] == r[pos2])
			ct--;
			r[pos2]=s[i];
			if (t[pos2] == r[pos2])
			ct++;
			pos2++;
		}
	}
	if (ct == n/2){
		ans++;
		if (ans > 1 && t != anss)
		ok=true;
		else
		if (ans == 1)
		anss=t;
	}
	if (ok) printf("NOT UNIQUE\n");
	else if (ans == 0) printf("NOT POSSIBLE\n");
	else printf("%d\n",anss);
	return 0;
}

Compilation message (stderr)

friends.cpp: In function 'int main()':
friends.cpp:9:14: warning: format '%s' expects argument of type 'char*', but argument 3 has type 'std::string' {aka 'std::__cxx11::basic_string<char>'} [-Wformat=]
    9 |    scanf("%d%s",&n,s);
      |             ~^      ~
      |              |      |
      |              char*  std::string {aka std::__cxx11::basic_string<char>}
friends.cpp:61:16: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::string' {aka 'std::__cxx11::basic_string<char>'} [-Wformat=]
   61 |  else printf("%d\n",anss);
      |               ~^        ~
      |                |        |
      |                int      std::string {aka std::__cxx11::basic_string<char>}
friends.cpp:9:9: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 |    scanf("%d%s",&n,s);
      |    ~~~~~^~~~~~~~~~~~~

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