poj 2408 Anagram Groups

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <set>
#define MAX 30001
using namespace std;
struct group {
    int num;
    set<string> gr;
    group() {
        num = 0;
    }
}g[MAX];
int trie[MAX * 100][26],to[MAX * 100];
int pos,num;
int snum[26];
bool cmp(const group &a,const group &b) {///注意这里
    if(a.num == b.num) return *(a.gr.begin()) < *(b.gr.begin());
    return a.num > b.num;
}
void Insert(char *s) {
    int len = strlen(s);
    string s1 = s;
    string s2 = "";
    for(int i = 0;s[i];i ++) {
        snum[s[i] - ‘a‘] ++;
    }
    for(int i = 0;i < 26;i ++) {
        while(snum[i]) {
            s2 += ‘a‘ + i;
            snum[i] --;
        }
    }
    int i = 0,c = 0;
    while(i < len) {
        int d = s2[i] - ‘a‘;
        if(!trie[c][d]) trie[c][d] = ++ pos;
        c = trie[c][d];
        i ++;
    }
    if(!to[c]) to[c] = ++ num;
    g[to[c]].gr.insert(s1) ;
    g[to[c]].num ++;
}

int main() {
    char str[100];
    while(~scanf("%s",str)) {
        Insert(str);
    }
    sort(g + 1,g + 1 + num,cmp);
    for(int i = 1;i <= 5;i ++) {
        printf("Group of size %d:",g[i].num);
        for(set<string>::iterator it = g[i].gr.begin();it != g[i].gr.end();it ++) {
            printf(" %s",(*it).c_str());
        }
        puts(" .");
    }
}