Submission #1222705

#	Time	Username	Problem	Language	Result	Execution time	Memory
1222705		sleepntsheep	Prize (CEOI22_prize)	C++17	0 / 100	760 ms	102220 KiB

Main

#include <stdio.h>


#define N 1000000

int n, k, q, t, p[N], dfn[N], dfc, nfd[N], fa[N], hd[N], e[N * 2]
, Ln[N * 2], ii, rt, hld[N], lv[N], dis[N], sz[N];

void add(int u, int v) {
	++ii;
	e[ii] = v, Ln[ii] = hd[u];
	hd[u] = ii;
}

void dfs(int u) {
	sz[u] = 1;
	for (int v, j = hd[u]; j; j = Ln[j]) {
		v = e[j];
		lv[v] = lv[u] + 1;
		dfs(v);
		sz[u] += sz[v];
		if (sz[v] > sz[e[hd[u]]]) e[j] = e[hd[u]], e[hd[u]] = v;
	}
}

void dfs2(int u) {
	nfd[dfn[u] = dfc++] = u;
	for (int v, j = hd[u]; j; j = Ln[j]) {
		v = e[j];
		hld[v] = j == hd[u] ? hld[u]: v;
		dfs2(v);
	}
}

int lca(int u, int v) {
	while (hld[u] != hld[v]) {
		if (lv[hld[u]] > lv[hld[v]]) u = fa[hld[u]];
		else v = fa[hld[v]];
	}
	return dfn[u] < dfn[v] ? u: v;
}

int main() {
	scanf("%d%d%d%d", &n, &k, &q, &t);

	for (int i = 0; i < n; ++i) {
		scanf("%d", &fa[i]);
		if (fa[i] == -1)
			rt = i;
		else
			add(--fa[i], i);
	}

	for (int i = 0; i < n; ++i) scanf("%*d");

	fa[rt] = rt;	hld[rt] = rt;
	dfs(rt);
	dfs2(rt);

	for (int i = 0; i < k; ++i)
		printf("%d ", 1 + nfd[i]);
	puts("");
	fflush(stdout);
	for (int i = 1; i <= q; ++i)
		printf("? %d %d\n", 1 + rt, 1 + nfd[i]);
	puts("!");
	fflush(stdout);

	for (int i = 1; i <= q; ++i)
		scanf("%*d%d%*d%*d\n", dis + nfd[i]);

	for (int i = 0; i < t; ++i) {
		int u, v;
		scanf("%d%d", &u, &v), --u, --v;
		int x = dis[u] + dis[v] - 2 * dis[lca(u, v)];
		printf("%d %d\n", x, x);
	}
	fflush(stdout);

	return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:44:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |         scanf("%d%d%d%d", &n, &k, &q, &t);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:47:22: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |                 scanf("%d", &fa[i]);
      |                 ~~~~~^~~~~~~~~~~~~~
Main.cpp:54:42: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   54 |         for (int i = 0; i < n; ++i) scanf("%*d");
      |                                     ~~~~~^~~~~~~
Main.cpp:70:22: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   70 |                 scanf("%*d%d%*d%*d\n", dis + nfd[i]);
      |                 ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:74:22: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   74 |                 scanf("%d%d", &u, &v), --u, --v;
      |                 ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 25
• Subtask 3: 0 / 19
• Subtask 4: 0 / 22
• Subtask 5: 0 / 24