zoj 1492 Maximum Clique

最大团算法模板

#include
#include
#include
#include
#define maxn 1001
#define INF 10000000
using namespace std;
int g[51][51], alt[51][51], Max[51], res;
bool dfs(int cur, int tot) {
	if (!cur) {
		if (tot > res) {
			res = tot;
			return 1;
		}
		return 0;
	}
	int i, j, u, nxt;
	for (i = 1; i <= cur; i++) {
		if (cur - i + 1 + tot <= res)return 0;
		u = alt[tot][i];
		if (Max[u] + tot <= res)return 0;
		nxt = 0;
		for (j = i + 1; j <= cur; j++) {
			if (g[u][alt[tot][j]])alt[tot + 1][++nxt] = alt[tot][j];
		}
		if (dfs(nxt, tot + 1))return 1;
	}
	return 0;
}
void solve(int n) {
	int i, j, cur;
	for (i = n; i; i--) {
		cur = 0;
		for (j = i + 1; j <= n; j++) { 
			if (g[i][j])alt[1][++cur] = j;
		}
		dfs(cur, 1);
		Max[i]=res;
	}
}
int main() {
	int n, i, j;
	while (scanf("%d", &n) && n) {
		for (i = 1; i <= n; i++) {
			for (j = 1; j <= n; j++) {
				scanf("%d", &g[i][j]);
			}
		}
		res = 0;
		solve(n);
		printf("%d\n", res);
	}
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53