hdu 1004(hash)

//hash
#include <cstdio>
#include <cstring>
#include <iostream>

using namespace std;

const int M = 1361;

struct node {//节点
    char str[16];
    int count;
    node *next;
}s[M];

int maxs;
char ans[16];

void init() {//初始化
    for (int i=0; i<M; ++i) {
        s[i].next = NULL;
        s[i].count = 0;
    }
}

unsigned int BKDRHash(char str[]) {//hash
    unsigned int seed = 131;
    unsigned int hash = 0;
    while (*str) hash = hash * seed + (*str++);
    return (hash & 0x7FFFFFFF);
}

void solve(char ch[]) {
    int k = BKDRHash(ch) % M;
    node *p, *q;
    p = s[k].next;
    while (p != NULL) {
        if (strcmp(p->str, ch) == 0) {
            ++p->count;
            if (maxs < p->count) {
                maxs = p->count;
                strcpy(ans, p->str);
            }
            return ;
        }
        p = p->next;
    }
    q = new node;
    q->count = 1;
    q->next = NULL;
    strcpy(q->str, ch);
    q->next = s[k].next;
    s[k].next = q;
    if (maxs < q->count) {
        maxs = q->count;
        strcpy(ans, q->str);
    }
    return ;
}

void del(node *p) {//释放内存
    if (p == NULL) return ;
    del(p->next);
    delete p;
}

int main() {
    int n;
    char ch[16];
    while (scanf("%d", &n), n) {
        init();
        maxs = -1;
        for (int i=0; i<n; ++i) {
            scanf ("%s", ch);
            solve(ch);
        }
        for (i=0; i<n; ++i) {
            if (s[i].next != NULL) del(s[i].next); 
        }
        printf ("%s\n", ans);
    }
    return 0;
}