改为不用tarjan求SSC#includealgorithm#includeiostream#includecstring#includecstdio#includecmathusing namespace std;const int MAXN=2e3+5MAXM=MAXNMAXN;int nmtotheadMAXN;struct Edge int tonxt; Edge to=nxt=0;

#include #include #include #include #include using namespace std;

const int MAXN = 2e3 + 5, MAXM = MAXN * MAXN; int n, m, tot, head[MAXN]; struct Edge { int to, nxt; Edge() { to = nxt = 0; } Edge(int x, int y) { to = x, nxt = y; } } edge[MAXM]; void Add(int u, int v) { edge[++tot] = {v, head[u]}; head[u] = tot; }

int top, cnt, dfc, dfn[MAXN], low[MAXN], stck[MAXN]; bool vis[MAXN]; void tarjan(int u) {
dfn[u] = low[u] = ++dfc; stck[++top] = u; vis[u] = true; for (int i = head[u]; i != 0; i = edge[i].nxt) { int v = edge[i].to; if (!dfn[v]) { tarjan(v); low[u] = min(low[u], low[v]); } else if (vis[v]) { low[u] = min(low[u], low[v]); } } if (dfn[u] == low[u]) { cnt++; for (int v = stck[top]; top--; v = stck[top]) { vis[v] = false; if (u == v) return ; } } }

void solve() { memset(head, 0, sizeof head);
while (m--) { int u, v; scanf("%d%d", &u, &v); int op; scanf("%d", &op); if (op == 1) Add(u, v);
else Add(u, v), Add(v, u);
} memset(dfn, 0, sizeof dfn); memset(low, 0, sizeof low); memset(vis, false, sizeof vis); cnt = dfc = top = 0;
for (int i = 1; i <= n && cnt < 2; i++) if (!dfn[i]) tarjan(i); printf("%d\n", cnt == 1); }

int main() { for (scanf("%d%d", &n, &m); n || m; scanf("%d%d", &n, &m)) solve(); return 0; }