POJ 1523

题目大意

暂无

题目解法

暂无

RTFC

#include <cstdio>
#include <cctype>
#include <cstring>
#define clz(X) memset(X, 0, sizeof(X))
inline int max(int a, int b) { return a > b ? a : b; }
inline int min(int a, int b) { return a < b ? a : b; }
inline void read(int &x)
{
    int ch = x = 0;
    while (!isdigit(ch = getchar()));
    for (; isdigit(ch); ch = getchar())
        x = x * 10 + ch - '0';
}
int map[1010][1010], range;
int dfn[1010], low[1010], idx;
int son, subnet[1010];
void tarjan(int u)
{
    dfn[u] = low[u] = ++idx;
    for (int v = 1; v <= range; v++)
        if (map[u][v])
            if (!dfn[v])
            {
                tarjan(v);
                low[u] = min(low[u], low[v]);
                if (low[v] >= dfn[u])
                    (u == 1 ? son : subnet[u])++;
            }
            else
                low[u] = min(low[u], dfn[v]);
}
int main()
{
    int x, y, T = 0;
    while (read(x), x)
    {
        clz(map), clz(dfn), clz(low), clz(subnet), son = idx = 0;
        read(y);
        map[x][y] = map[y][x] = 1;
        range = max(x, y);
        while (read(x), x)
        {
            read(y);
            map[x][y] = map[y][x] = 1;
            range = max(range, max(x, y));
        }
        printf("Network #%d\n", ++T);
        tarjan(1);
        bool flag = false;
        if (son > 1) subnet[1] = son - 1;
        for (int i = 1; i <= range; i++)
            if (subnet[i])
                printf("  SPF node %d leaves %d subnets\n", i, subnet[i] + 1),
                flag = true;
        if (!flag)
            puts("  No SPF nodes");
        putchar('\n');
    }
    return 0;
}