HDU 4324--Triangle Love "topology sort && adjacency Table implementation"

Triangle LoveTime limit:2000/1000 MS (java/others) Memory limit:65536/65536 K (java/others)
Total submission (s): 3496 Accepted Submission (s): 1357


Problem descriptionrecently, scientists find that there was love between any of the people. For example, between A and B, if a don ' t love B, then B must love A, vice versa. And there is the no possibility that the people love each other, what a crazy world!
Now, scientists want to know whether or not there are a "Triangle love" among N people. "Triangle Love" means this among any three people (b and C), A loves B, B loves C and C loves A.
Your problem is writing a program to read the relationship among N people firstly, and return whether or not there is a "T Riangle Love ".

Inputthe first line contains a single integer t (1 <= t <=), the number of test cases.
For each case, the first line contains one integer N (0 < N <= 2000).
In the next N lines contain the adjacency matrix A of the the relationship (without spaces). Ai,j = 1 means i-th people loves j-th people, otherwise ai,j = 0.
It is guaranteed that the given relationship is a tournament, which is, ai,i= 0, Ai,j≠aj,i (1<=i, j<=n,i≠j).
Outputfor each case, output the case number as shown and then print ' Yes ', if there is a ' Triangle love ' among these N PEO PLE, otherwise print "No".
Take the sample output for more details.

Sample Input

25001001000001001111011100050111100000010000110001110

Sample Output

Case #1: yescase #2: No

Main topic:
T Group test data, each group of data a n represents n individuals, and then the matrix of N*n to represent the relationship between these people, input must meet if a does not like B, B must like a, and will not appear a and b mutually like the situation, ask you whether there is a triangle love.

Problem Solving Ideas:
After topological sorting, it is necessary to determine whether there is a ring, and there is a triangle love.

#include <cstdio> #include <cstring> #include <algorithm> #include <queue> #define MAXN 2010using namespace Std;char map[maxn];int indu[maxn];int HEAD[MAXN], cnt;int N, k;struct node {int u, V, next;};    Node EDGE[MAXN * maxn];void init () {cnt = 0;    Memset (Head,-1, sizeof (head)); memset (indu, 0, sizeof (INDU));}    void Add (int u, int v) {edge[cnt] = {u, V, Head[u]}; Head[u] = cnt++;}    void input () {scanf ("%d", &n);        for (int i = 0; i < n; ++i) {scanf ("%s", map);                for (int j = 0; J < N; ++j) if (map[j] = = ' 1 ') {Add (I, j);            indu[j]++;    }}}void Topsort () {printf ("Case #%d:", ++k);    Queue<int >q;    int ans = 0;            for (int i = 0; i < n; ++i) {if (!indu[i]) {Q.push (i);        ans++;        }} while (!q.empty ()) {int u = q.front ();        Q.pop ();     for (int i = head[u]; i =-1; i = edge[i].next) {int v = EDGE[I].V;       indu[v]--;                if (!indu[v]) {Q.push (v);            ans++;    }}} if (n = = ans) printf ("no\n"); else printf ("yes\n");}    int main () {int T;    scanf ("%d", &t);    k = 0;        while (t--) {init ();        Input ();    Topsort (); } return 0;}

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

HDU 4324--Triangle Love "topology sort && adjacency Table implementation"