树 2016.8.23

1、二叉排序树

描述

依次给出n(0<n<=100000)个整数，请你以这n个数创建一棵二叉排序树，这棵排序树的根节点为第一个数，并输出其中序遍历和后序遍历。

输入

共两行，第一行为整数n，第二行为n个整数

输出

共两行，第一行为中序遍历，第二行为后序遍历

样例输入

823 45 12 6 7 89 13 47

样例输出

6 7 12 13 23 45 47 89 7 6 13 12 47 89 45 23

#include <iostream>#include <cstdio>#include <cstring>#include <cstdlib>#include <algorithm>#include <queue>#include <vector>#include <stack>#include <map>#include <cmath>#include <cctype>using namespace std;typedef long long ll;typedef unsigned long long ull;typedef unsigned int uint;const ull mod = 1e9 + 7;const int INF = 0x3f3f3f3f;const int maxn = 1e5 + 10;int n;int num[maxn];int Count = 0;struct BST {    int key;    BST* Left;    BST* Right;};typedef BST *bst;void Insert(bst root, int key);void Printf(bst root);int main(){#ifdef __AiR_H    freopen("in.txt", "r", stdin);#endif // __AiR_H    scanf("%d", &n);    scanf("%d", &num[0]);    bst root = (bst)malloc(sizeof(BST));    root->key = num[0];    root->Left = root->Right = NULL;    for (int i = 1; i < n; ++i) {        scanf("%d", &num[i]);        Insert(root, num[i]);    }    sort(num, num+n);    printf("%d", num[0]);    for (int i = 1; i < n; ++i) {        printf(" %d", num[i]);    }    printf("\n");    Printf(root);    printf("\n");    return 0;}void Insert(bst root, int key){    bst t = (bst)malloc(sizeof(BST));    t->key = key;    t->Left = t->Right = NULL;    if (key < root->key) {        if (root->Left == NULL) {            root->Left = t;            return;        } else {            Insert(root->Left, key);        }    } else {        if (root->Right == NULL) {            root->Right = t;            return;        } else {            Insert(root->Right, key);        }    }}void Printf(bst root){    if (root == NULL) {        return;    }    Printf(root->Left);    Printf(root->Right);    printf(++Count == 1 ? "%d" : " %d", root->key);}

2、打牌

#include <iostream>#include <cstdio>#include <cstring>#include <cstdlib>#include <algorithm>#include <queue>#include <vector>#include <stack>#include <map>#include <cmath>#include <cctype>#include <bitset>#include <ctime>#include <ext/pb_ds/assoc_container.hpp>using namespace std;using namespace __gnu_pbds;#define REP(i, n) for (int i = 0; i < (n); ++i)typedef long long ll;typedef unsigned long long ull;typedef unsigned int uint;typedef pair<int, int> Pair;typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> SuperTree;const ull mod = 1e9 + 7;const int INF = 0x7fffffff;const int maxn = 1e5 + 10;int num[maxn];int N, M;char cmd[10];int cmd_num;SuperTree Tree;map<int, int> Map;int main(){#ifdef __AiR_H    freopen("in.txt", "r", stdin);#endif // __AiR_H    Map.clear();    scanf("%d %d", &N, &M);    for (int i = 0; i < N; ++i) {        scanf("%d", &num[i]);        Map[num[i]] = 1;        Tree.insert(num[i]);    }    int Size = N;    while (M--) {        scanf("%s %d", cmd, &cmd_num);        if (cmd[0] == 'i') {            ++Size;            Map[cmd_num] = 1;            Tree.insert(cmd_num);        } else if (cmd[0] == 'd') {            if (Map[cmd_num] != 0) {                --Size;                Tree.erase(cmd_num);                Map[cmd_num] = 0;            } else {                printf("invalid number!\n");            }        } else {            if (cmd_num > Size) {                printf("invalid K!\n");            } else {                printf("%d\n", *Tree.find_by_order(Size - cmd_num));            }        }    }    return 0;}

3、UVa 548 Tree

题意：

给出中序遍历和后序遍历，输出最小路径的叶子结点

#include <iostream>#include <cstdio>#include <cstring>#include <cstdlib>#include <algorithm>#include <queue>#include <vector>#include <stack>#include <map>#include <cmath>#include <cctype>#include <bitset>#include <ctime>using namespace std;#define REP(i, n) for (int i = 0; i < (n); ++i)typedef long long ll;typedef unsigned long long ull;typedef unsigned int uint;typedef pair<int, int> Pair;const ull mod = 1e9 + 7;const int INF = 0x7fffffff;const int maxn = 1e4 + 10;int Count = 1;int num[maxn * 2];struct Tree {    int Left, Right;};Tree tree[maxn];int Min = INF;int ans = 0;int Build(int Post_low, int Post_high, int In_low, int In_high);void dfs(int root, int sum);int main(){#ifdef __AiR_H    freopen("in.txt", "r", stdin);#endif // __AiR_H    while (scanf("%d", &num[1]) == 1) {        Count = 2;        while (getchar() != '\n') {            scanf("%d", &num[Count++]);        }        scanf("%d", &num[Count++]);        while (getchar() != '\n') {            scanf("%d", &num[Count++]);        }        Count -= 1;        int nodes = Count / 2;        int root = Build(nodes+1, Count, 1, nodes);        Min = INF;        dfs(root, root);        printf("%d\n", ans);    }    return 0;}int Build(int Post_low, int Post_high, int In_low, int In_high){    if (In_low > In_high) {        return 0;    }    int root = num[Post_high];    int Pos = In_low;    while (num[Pos] != root) {        ++Pos;    }    int Count = Pos - In_low;    tree[root].Left = Build(Post_low, Post_low+Count-1, In_low, Pos-1);    tree[root].Right = Build(Post_low+Count, Post_high-1, Pos+1, In_high);    return root;}void dfs(int root, int sum){    if (tree[root].Left == tree[root].Right && tree[root].Left == 0) {        if (sum < Min) {            Min = sum;            ans = root;        }        return;    }    if (tree[root].Left != 0) {        dfs(tree[root].Left, sum+tree[root].Left);    }    if (tree[root].Right != 0) {        dfs(tree[root].Right, sum+tree[root].Right);    }}

4、UVa 10562  Undraw the Trees

注意：

①结点不一定是数字和字母

②当前行的字符串长度可能小于上一行

#include <iostream>#include <cstdio>#include <cstring>#include <cstdlib>#include <algorithm>#include <queue>#include <vector>#include <stack>#include <map>#include <cmath>#include <cctype>#include <bitset>#include <ctime>using namespace std;#define REP(i, n) for (int i = 0; i < (n); ++i)typedef long long ll;typedef unsigned long long ull;typedef unsigned int uint;typedef pair<int, int> Pair;const ull mod = 1e9 + 7;const int INF = 0x7fffffff;const int maxn = 200 + 10;char s[maxn][maxn];int High = 1;int len[maxn];void dfs(int depth, int low, int high);int main(){#ifdef __AiR_H    freopen("in.txt", "r", stdin);//    freopen("out.txt", "w", stdout);#endif // __AiR_H    int T;    scanf("%d", &T);    getchar();    while (T--) {        High = 0;        memset(s, ' ', sizeof(s));        while (gets(s[High]) && s[High][0] != '#') {            len[High] = strlen(s[High]);            ++High;        }        High -= 1;        printf("(");        dfs(0, 0, len[0]-1);        printf(")\n");    }    return 0;}void dfs(int depth, int low, int high){    if (depth > High) {        return;    }    for (int i = low; i <= high; ++i) {        if (i < len[depth] && s[depth][i] != '-' && s[depth][i] != '|' && s[depth][i] != ' ' && s[depth][i] != '#') {            printf("%c", s[depth][i]);            if (s[depth+1][i] == '|') {                printf("(");                int low = i, high = i;                while (low-1 >= 0 && s[depth+2][low-1] == '-') {                    --low;                }                while (s[depth+2][high+1] == '-') {                    ++high;                }                dfs(depth+3, low, high);                printf(")");            } else {                printf("()");            }        }    }}

5、HDU 3791 二叉搜索树

#include <iostream>#include <cstdio>#include <cstring>#include <cstdlib>#include <algorithm>#include <queue>#include <vector>#include <stack>#include <map>#include <cmath>#include <cctype>#include <bitset>#include <ctime>using namespace std;#define REP(i, n) for (int i = 0; i < (n); ++i)typedef long long ll;typedef unsigned long long ull;typedef unsigned int uint;typedef pair<int, int> Pair;const ull mod = 1e9 + 7;const int INF = 0x7fffffff;const int maxn = 20;char key[maxn], t[maxn];int ans1[maxn], ans2[maxn];struct BST {    int Left, Right;};BST bst[maxn];void Insert(int root, int x);void bfs(int root, int num);int main(){#ifdef __AiR_H    freopen("in.txt", "r", stdin);#endif // __AiR_H    int n;    while (scanf("%d", &n) != EOF && n != 0) {        memset(bst, -1, sizeof(bst));        scanf("%s", key);        int root = key[0] - '0';        int len_key = strlen(key);        for (int i = 1; i < len_key; ++i) {            Insert(root, key[i] - '0');        }        bfs(root, 1);        while (n--) {            scanf("%s", t);            bool flag = true;            root = t[0] - '0';            memset(bst, -1, sizeof(bst));            for (int i = 1; i < len_key; ++i) {                Insert(root, t[i] - '0');            }            bfs(root, 2);            for (int i = 0; i < len_key; ++i) {                if (ans1[i] != ans2[i]) {                    flag = false;                    break;                }            }            if (flag) {                printf("YES\n");            } else {                printf("NO\n");            }        }    }    return 0;}void Insert(int root, int x){    if (x < root) {        if (bst[root].Left == -1) {            bst[root].Left = x;            return;        } else {            Insert(bst[root].Left, x);        }    } else {        if (bst[root].Right == -1) {            bst[root].Right = x;            return;        } else {            Insert(bst[root].Right, x);        }    }}void bfs(int root, int num){    queue<int> Q;    Q.push(root);    int Count = 0;    while (!Q.empty()) {        int t = Q.front();        Q.pop();        (num == 1) ? ans1[Count++] = t : ans2[Count++] = t;        if (bst[t].Left != -1) {            Q.push(bst[t].Left);        }        if (bst[t].Right != -1) {            Q.push(bst[t].Right);        }    }}