POJ 5326 - Work


Problem - 5326
It's an interesting experience to move from ICPC to work, end my college life and start a brand new journey in company.
As is known to all, every stuff in a company has a title, everyone except the boss has a direct leader, and all the relationship forms a tree. If A's title is higher than B(A is the direct or indirect leader of B), we call it A manages B.
Now, give you the relation of a company, can you calculate how many people manage k people.

Input
There are multiple test cases.
Each test case begins with two integers n and k, n indicates the number of stuff of the company.
Each of the following n-1 lines has two integers A and B, means A is the direct leader of B.

1 <= n <= 100 , 0 <= k < n
1 <= A, B <= n
Output
For each test case, output the answer as described above.

Sample Input
7 2 1 2 1 3 2 4 2 5 3 6 3 7 
Sample Output
2


这个题目是个递推,不过由于是树形的,需要dfs来完成递推的过程。
关键在于p[now] += p[to]+1;如果now能manage to的话。

此处采用链式前向星来保存关系图。
http://blog.csdn.net/tc_to_top/article/details/47108595
  1. struct EDGE  
  2. {  
  3.     int v, next;  
  4. }e[MAX];  
  5. int head[MAX], num[MAX];  
  6. bool in[MAX], vis[MAX];  
  7. int cnt, ans;  
  8. int n, k;  
  9.   
  10. void Add(int u, int v)  
  11. {  
  12.     e[cnt].v = v;  
  13.     e[cnt].next = head[u];  
  14.     head[u] = cnt ++;  
  15. }  
  16.   
  17. void DFS(int u)  
  18. {  
  19.     vis[u] = true;  
  20.     num[u] = 0;  
  21.     for(int i = head[u]; i != -1; i = e[i].next)  
  22.     {  
  23.         int v = e[i].v;  
  24.         if(!vis[v])  
  25.         {  
  26.             DFS(v);  
  27.             num[u] += (num[v] + 1);  
  28.         }  
  29.     }  
  30.     if(num[u] == k)  
  31.         ans ++;  
  32.     return;  
  33. }  
  34.   
  35. int main()  
  36. {  
  37.     while(scanf("%d %d", &n, &k) != EOF)  
  38.     {  
  39.         cnt = 0;  
  40.         ans = 0;  
  41.         memset(head, -1, sizeof(head));  
  42.         memset(in, falsesizeof(in));  
  43.         memset(vis, falsesizeof(vis));  
  44.         for(int i = 0; i < n - 1; i++)  
  45.         {  
  46.             int u, v;  
  47.             scanf("%d %d", &u, &v);  
  48.             Add(u, v);  
  49.             in[v] ++;  
  50.         }  
  51.         for(int i = 1; i <= n; i++)  
  52.             if(in[i] == 0)  
  53.                 DFS(i);  
  54.         printf("%d\n", ans);  
  55.     }  
  56. }  
X. DFS + DP
http://blog.csdn.net/firenet1/article/details/47129831
  1. vector<int>haha[200];  
  2. int check[200];  
  3. int num[200];  
  4. int dfs(int u){  
  5.     if(check[u]) return num[u]+1;  
  6.     check[u] = 1;  
  7.     for(int i = 0; i < haha[u].size();i++)  
  8.         num[u] += dfs(haha[u][i]);  
  9.     return num[u]+1;  
  10. }  
  11.   
  12.   
  13. int main(){  
  14.     int n,k;  
  15.     while(scanf("%d%d",&n,&k)!=EOF){  
  16.         for(int i = 0;i <= n; i++)  
  17.             haha[i].clear();  
  18.         int u,v;  
  19.         for(int i =1;i < n; i++){  
  20.             scanf("%d%d",&u,&v);  
  21.             haha[u].push_back(v);  
  22.         }  
  23.         memset(check,0,sizeof(check));  
  24.         memset(num,0,sizeof(num));  
  25.         int ans = 0;  
  26.         for(int i = 1;i <= n; i++){  
  27.   
  28.             if(check[i]) continue;  
  29.             dfs(i);  
  30.         }  
  31.         for(int i =1;i <= n; i++)  
  32.             if(num[i]==k) ans++;  
  33.         cout<<ans<<endl;  
  34.     }  
  35.     return 0;  
http://www.cnblogs.com/qq-star/p/4686536.html
int dfs(int x)
10 {
11     int sum=0;
12     for (int i=1;i<=n;i++)
13     {
14         if (Map[x][i]==1)
15         {
16             sum++;
17             sum+=dfs(i);
18         }
19     }
20     return sum;
21 }
22 
23 int main()
24 {
25     int a,b,ans;
26     while (~scanf("%d%d",&n,&m))
27     {
28         ans=0;
29         memset(Map,0,sizeof(Map));
30         //memset(ok,0,sizeof(ok));
31         for (int i=1; i<=n-1; i++)
32         {
33             scanf("%d%d",&a,&b);
34             Map[a][b]=1;
35         }
36         for (int i=1;i<=n;i++)
37         {
38             if (dfs(i)==m)
39                 ans++;
40         }
41         printf ("%d\n",ans);
42     }
43     return 0;
44 }
X. Reclusive solution - not efficient
http://www.zgxue.com/198/1980697.html
struct node
{
 int num,s[105];
}res[105];
int ans;
void judge(int i)
{
 if(res[i].num==0)
     return ;
 ans+=res[i].num;
 for(int j=0;j<res[i].num;j++)
     judge(res[i].s[j]);
}
int main()
{
 int n,k,a,b,cnt;
 while(~scanf("%d%d",&n,&k))
 {
  memset(res,0,sizeof(res));
  for(int i=0;i<n-1;i++)
  {
   scanf("%d%d",&a,&b);
   res[a].s[res[a].num]=b;
   res[a].num++;
  }
  cnt=0;
  for(int i=1;i<=n;i++)
  {
   ans=res[i].num;
   for(int j=0;j<res[i].num;j++)
       judge(res[i].s[j]);
            if(ans==k)
                cnt++;
  }
  printf("%d\n",cnt);
 }
 return 0;
}
Read full article from Problem - 5326

Labels

LeetCode (1432) GeeksforGeeks (1122) LeetCode - Review (1067) Review (882) Algorithm (668) to-do (609) Classic Algorithm (270) Google Interview (237) Classic Interview (222) Dynamic Programming (220) DP (186) Bit Algorithms (145) POJ (141) Math (137) Tree (132) LeetCode - Phone (129) EPI (122) Cracking Coding Interview (119) DFS (115) Difficult Algorithm (115) Lintcode (115) Different Solutions (110) Smart Algorithm (104) Binary Search (96) BFS (91) HackerRank (90) Binary Tree (86) Hard (79) Two Pointers (78) Stack (76) Company-Facebook (75) BST (72) Graph Algorithm (72) Time Complexity (69) Greedy Algorithm (68) Interval (63) Company - Google (62) Geometry Algorithm (61) Interview Corner (61) LeetCode - Extended (61) Union-Find (60) Trie (58) Advanced Data Structure (56) List (56) Priority Queue (53) Codility (52) ComProGuide (50) LeetCode Hard (50) Matrix (50) Bisection (48) Segment Tree (48) Sliding Window (48) USACO (46) Space Optimization (45) Company-Airbnb (41) Greedy (41) Mathematical Algorithm (41) Tree - Post-Order (41) ACM-ICPC (40) Algorithm Interview (40) Data Structure Design (40) Graph (40) Backtracking (39) Data Structure (39) Jobdu (39) Random (39) Codeforces (38) Knapsack (38) LeetCode - DP (38) Recursive Algorithm (38) String Algorithm (38) TopCoder (38) Sort (37) Introduction to Algorithms (36) Pre-Sort (36) Beauty of Programming (35) Must Known (34) Binary Search Tree (33) Follow Up (33) prismoskills (33) Palindrome (32) Permutation (31) Array (30) Google Code Jam (30) HDU (30) Array O(N) (29) Logic Thinking (29) Monotonic Stack (29) Puzzles (29) Code - Detail (27) Company-Zenefits (27) Microsoft 100 - July (27) Queue (27) Binary Indexed Trees (26) TreeMap (26) to-do-must (26) 1point3acres (25) GeeksQuiz (25) Merge Sort (25) Reverse Thinking (25) hihocoder (25) Company - LinkedIn (24) Hash (24) High Frequency (24) Summary (24) Divide and Conquer (23) Proof (23) Game Theory (22) Topological Sort (22) Lintcode - Review (21) Tree - Modification (21) Algorithm Game (20) CareerCup (20) Company - Twitter (20) DFS + Review (20) DP - Relation (20) Brain Teaser (19) DP - Tree (19) Left and Right Array (19) O(N) (19) Sweep Line (19) UVA (19) DP - Bit Masking (18) LeetCode - Thinking (18) KMP (17) LeetCode - TODO (17) Probabilities (17) Simulation (17) String Search (17) Codercareer (16) Company-Uber (16) Iterator (16) Number (16) O(1) Space (16) Shortest Path (16) itint5 (16) DFS+Cache (15) Dijkstra (15) Euclidean GCD (15) Heap (15) LeetCode - Hard (15) Majority (15) Number Theory (15) Rolling Hash (15) Tree Traversal (15) Brute Force (14) Bucket Sort (14) DP - Knapsack (14) DP - Probability (14) Difficult (14) Fast Power Algorithm (14) Pattern (14) Prefix Sum (14) TreeSet (14) Algorithm Videos (13) Amazon Interview (13) Basic Algorithm (13) Codechef (13) Combination (13) Computational Geometry (13) DP - Digit (13) LCA (13) LeetCode - DFS (13) Linked List (13) Long Increasing Sequence(LIS) (13) Math-Divisible (13) Reservoir Sampling (13) mitbbs (13) Algorithm - How To (12) Company - Microsoft (12) DP - Interval (12) DP - Multiple Relation (12) DP - Relation Optimization (12) LeetCode - Classic (12) Level Order Traversal (12) Prime (12) Pruning (12) Reconstruct Tree (12) Thinking (12) X Sum (12) AOJ (11) Bit Mask (11) Company-Snapchat (11) DP - Space Optimization (11) Dequeue (11) Graph DFS (11) MinMax (11) Miscs (11) Princeton (11) Quick Sort (11) Stack - Tree (11) 尺取法 (11) 挑战程序设计竞赛 (11) Coin Change (10) DFS+Backtracking (10) Facebook Hacker Cup (10) Fast Slow Pointers (10) HackerRank Easy (10) Interval Tree (10) Limited Range (10) Matrix - Traverse (10) Monotone Queue (10) SPOJ (10) Starting Point (10) States (10) Stock (10) Theory (10) Tutorialhorizon (10) Kadane - Extended (9) Mathblog (9) Max-Min Flow (9) Maze (9) Median (9) O(32N) (9) Quick Select (9) Stack Overflow (9) System Design (9) Tree - Conversion (9) Use XOR (9) Book Notes (8) Company-Amazon (8) DFS+BFS (8) DP - States (8) Expression (8) Longest Common Subsequence(LCS) (8) One Pass (8) Quadtrees (8) Traversal Once (8) Trie - Suffix (8) 穷竭搜索 (8) Algorithm Problem List (7) All Sub (7) Catalan Number (7) Cycle (7) DP - Cases (7) Facebook Interview (7) Fibonacci Numbers (7) Flood fill (7) Game Nim (7) Graph BFS (7) HackerRank Difficult (7) Hackerearth (7) Inversion (7) Kadane’s Algorithm (7) Manacher (7) Morris Traversal (7) Multiple Data Structures (7) Normalized Key (7) O(XN) (7) Radix Sort (7) Recursion (7) Sampling (7) Suffix Array (7) Tech-Queries (7) Tree - Serialization (7) Tree DP (7) Trie - Bit (7) 蓝桥杯 (7) Algorithm - Brain Teaser (6) BFS - Priority Queue (6) BFS - Unusual (6) Classic Data Structure Impl (6) DP - 2D (6) DP - Monotone Queue (6) DP - Unusual (6) DP-Space Optimization (6) Dutch Flag (6) How To (6) Interviewstreet (6) Knapsack - MultiplePack (6) Local MinMax (6) MST (6) Minimum Spanning Tree (6) Number - Reach (6) Parentheses (6) Pre-Sum (6) Probability (6) Programming Pearls (6) Rabin-Karp (6) Reverse (6) Scan from right (6) Schedule (6) Stream (6) Subset Sum (6) TSP (6) Xpost (6) n00tc0d3r (6) reddit (6) AI (5) Abbreviation (5) Anagram (5) Art Of Programming-July (5) Assumption (5) Bellman Ford (5) Big Data (5) Code - Solid (5) Code Kata (5) Codility-lessons (5) Coding (5) Company - WMware (5) Convex Hull (5) Crazyforcode (5) DFS - Multiple (5) DFS+DP (5) DP - Multi-Dimension (5) DP-Multiple Relation (5) Eulerian Cycle (5) Graph - Unusual (5) Graph Cycle (5) Hash Strategy (5) Immutability (5) Java (5) LogN (5) Manhattan Distance (5) Matrix Chain Multiplication (5) N Queens (5) Pre-Sort: Index (5) Quick Partition (5) Quora (5) Randomized Algorithms (5) Resources (5) Robot (5) SPFA(Shortest Path Faster Algorithm) (5) Shuffle (5) Sieve of Eratosthenes (5) Strongly Connected Components (5) Subarray Sum (5) Sudoku (5) Suffix Tree (5) Swap (5) Threaded (5) Tree - Creation (5) Warshall Floyd (5) Word Search (5) jiuzhang (5)

Popular Posts