poj2418(Hardwood Species)

// #pragma comment(linker, "/STACK:1024000000,1024000000")
#include <iostream>
#include <algorithm>
#include <iomanip>
#include <sstream>
#include <string>
#include <stack>
#include <queue>
#include <deque>
#include <vector>
#include <map>
#include <set>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <limits.h>
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int,int> ii;
// #define DEBUG
#ifdef DEBUG
#define debug(...) printf( __VA_ARGS__ )
#else
#define debug(...)
#endif
const int inf = 1 << 30;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
struct node{
node* nxt[256];
int cnt;
node(){
for (int i = 0;i < 256;i++)
nxt[i] = NULL;
cnt=0;
}
};
void insert(node* root,char* s){
node *p = root;
int len = strlen(s);
for (int i = 0;i < len;i++){
if (p->nxt[s[i]] == NULL) p->nxt[s[i]] = new node();
p = p->nxt[s[i]];
}
p->cnt++;
}
int n;
void dfs(node* root){
static char word[31];
static int pos;
int i;
if (root->cnt){
word[pos] = '\0';
if (word[0]){
printf("%s %.4f\n",word,(double)root->cnt * 100.0/n);
}
}
for (int i = 0;i < 256;i++){
if (root->nxt[i]){
debug("Find %c\n",i);
word[pos++] = i;
dfs(root->nxt[i]);
pos--;
debug("Back\n");
}
}
}
void del(node* root){
if (root == NULL) return;
for (int i = 0;i < 256;i++){
if (root->nxt[i]) del(root->nxt[i]);
}
delete root;
}
int main()
{
// freopen("in.txt","r",stdin);
// freopen("out.txt","w",stdout);
char s[1000010];
node* root = new node();
while(gets(s)){
insert(root,s);
n++;
}
dfs(root);
del(root);
return 0;
}