Submission #696050

#	Time	Username	Problem	Language	Result	Execution time	Memory
696050		happiansf	Three Friends (BOI14_friends)	C++17	0 / 100	1076 ms	8012 KiB

friends

#include<cstdio>
#include<algorithm>
#include<string>
using namespace std;

#define N 2000001

int n, cnt;
string a, x, y;



void input()
{
    char temp[N + 2];

    scanf("%d", &n);
    scanf("%s", temp);
    a = temp;
    a = "-" + a;
}

bool check(int s1, int e1, int s2, int e2)
{
    int sig = 0;

    for(int i = 0; i <= e1 - s1; i++)
    {
        //printf("------ %d %c %c\n", i, a[s1 + i], a[s2 + i + sig]);
        if(a[s1 + i] != a[s2 + i + sig])
        {

            if(sig)
            {
                return false;
            }
            sig++;
        }
    }
    return true;
}

void core()
{

    if(n % 2 == 0)
    {
        printf("NOT POSSIBLE");
        return;
    }

    if(check(1, n / 2, n / 2 + 1, n))
    {
        //printf("----------------------1\n");
        x = '-';
        for(int i = 1; i <= n / 2; i++)
        {
            x = x + a[i];
        }
        cnt++;
    }

    if(check(n / 2 + 2, n, 1, n / 2 + 1))
    {
        //printf("----------------------2\n");
        y = '-';
        for(int i = n / 2 + 2; i <= n; i++)
        {
            y = y + a[i];
        }
        cnt += 3;
    }
    //printf("-jsalkdak\n");
    if(cnt == 0)
    {
        printf("NOT POSSIBLE");
    }
    else if(cnt % 2)
    {
        if(cnt == 1)
        {
            printf("%s", &x.c_str()[1]);
        }
        else
        {
            printf("%s", &y.c_str()[1]);
        }
    }
    else
    {
        if(x == y)
        {
            printf("%s", &x.c_str()[1]);
        }
        else
        {
            printf("NOT UNIQUE");
        }
    }

    //printf("%s\n", a.c_str());
    //printf("%d", check(1, n / 2, n / 2 + 1, n));
}

int main()
{
    input();
    core();
    return 0;
}

Compilation message (stderr)

friends.cpp: In function 'void input()':
friends.cpp:17:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~
friends.cpp:18:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   18 |     scanf("%s", temp);
      |     ~~~~~^~~~~~~~~~~~

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