Submission #103522

#	Time	Username	Problem	Language	Result	Execution time	Memory
103522		pedro_sponchiado	Three Friends (BOI14_friends)	C++17	0 / 100	24 ms	7208 KiB

friends

#include<bits/stdc++.h>
using namespace std;
const int maxn=2000010;
int n_, n;
char str[maxn], s1[maxn], s2[maxn], s3[maxn], s4[maxn];
int mini;
 
int verif(char str1[maxn], char str2[maxn]){
	for(int i=0; i<=n; i++){
		if(str1[i]!=str2[i]){
			mini=i;
			break;	
		}
	}
//	printf("mini=%d\n", mini);
	
	int cont=0, da=1;
	for(int i=0; i<n; i++){
		if(cont==mini) cont++;
//		printf("%c %c\n", str1[i], str2[cont]);
		if(str1[i]!=str2[cont]) da=0;
		cont++;
	}
//	printf("%d\n", da);
	if(da==0) return 0;
//	if( (str2[mini]==str2[mini-1] && mini>=1) || (str2[mini]==str2[mini+1] && mini<=n-1) ) return 2;
	return 1;
}
 
int main(){
	scanf("%d", &n_);
	scanf(" %s ", str);
	if(n_%2==0){
		printf("NOT POSSIBLE\n");
		return 0;
	}
	n=n_/2;
	
	for(int i=0; i<n; i++) s1[i]=str[i];
	for(int i=n; i<=2*n; i++) s2[i-n]=str[i];
	for(int i=n+1; i<=2*n; i++) s3[i-n-1]=str[i];
	for(int i=0; i<=n; i++) s4[i]=str[i];
	
	int x=verif(s1, s2);
	int mini1=mini;
	int y=verif(s3, s4);
	int mini2=mini;
//	printf("%s %s %s %s\n", s1, s2, s3, s4);
	
	if(x+y==0) printf("NOT POSSIBLE\n");
	if(x+y==1){
		if(x==1) printf("%s\n", s1);
		else printf("%s\n", s3);
	}
	if(x+y==2){
	//	printf("%d %d %d %d\n", x, y, mini1, mini2);
		if(s1==s3) printf("%s\n", s1);
		else printf("NOT UNIQUE\n");
	}
	return 0;
}

Compilation message (stderr)

friends.cpp: In function 'int main()':
friends.cpp:45:6: warning: unused variable 'mini1' [-Wunused-variable]
  int mini1=mini;
      ^~~~~
friends.cpp:47:6: warning: unused variable 'mini2' [-Wunused-variable]
  int mini2=mini;
      ^~~~~
friends.cpp:31:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n_);
  ~~~~~^~~~~~~~~~~
friends.cpp:32:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf(" %s ", str);
  ~~~~~^~~~~~~~~~~~~

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