Submission #17600

#	Time	Username	Problem	Language	Result	Execution time	Memory
17600		Namnamseo	Three Friends (BOI14_friends)	C++98	100 / 100	26 ms	3036 KiB

friends

#include <cstdio>
 
char buf[2000010];
int count[26];
int target[26];
int n;
 
int main()
{
    scanf("%d",&n);
    int i;
    int len = (n-1)/2;
    scanf("%s",buf);
    for(i=0;i<n;++i) count[buf[i]-'A']++;
    int tmp=0, tmpi;
    for(i=0;i<26;++i){
        if(count[i]%2) ++tmp, tmpi=i;
    }
    if(tmp!=1){
        puts("NOT POSSIBLE");
        return 0;
    }
    tmp=0;
    for(i=0;i<26;++i){
        target[i]=(count[i]+1)/2;
        if(target[i]) ++tmp;
    }
    int zeroc=0;
    for(i=0;i<len;++i){
        --target[buf[i]-'A'];
        if(target[buf[i]-'A']==0) zeroc++;
    }
    bool a1, a2;
    int j;
    bool flag=false;
    for(i=0, j=len+1; j<n; ++i, ++j){
        if(buf[i+flag]!=buf[j]){
            if(flag) break;
            else flag=true;
        }
    }
    a1=(j==n);
    flag=false;
    for(i=0,j=len;i<len; ++i, ++j){
        if(buf[i]!=buf[j+flag]){
            if(flag) break;
            else flag=true;
        }
    }
    a2=(i==len);
    if(a1 && a2){
        for(i=0;i<len;i++){
            if(buf[i]!=buf[i+len+1]) break;
        }
        if(i==len) {
            puts(buf+len+1);
        }
        else puts("NOT UNIQUE");
    } else if(a1){
        puts(buf+len+1);
    } else if(a2){
        buf[len]=0;
        puts(buf);
    } else {
        puts("NOT POSSIBLE");
    }
    return 0;
}

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