poj2418(Hardwood Species)

思路：建立Tire树，dfs一遍，再del下。

// #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(...)#endifconst 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;}