#include <stdio.h>
#define N 100007
#define M 400007
int n, m, to[M], nx[M], st[N], low[N], vis[N], ts, stk[N], instack[N], *top = &stk[0];
int bto[N * 4], bnx[N * 4], bst[N * 2], b, bm, bsz[N * 2];
long long ans = 0;
inline void minimize(int &i, int j) { (i > j ? i = j : 0); }
void build(int u, int p)
{
low[u] = vis[u] = ++ts;
instack[*(++top) = u] = 1;
int i, v, c = 0;
for (i = st[u]; i; i = nx[i]) if (to[i] != p) {
v = to[i];
if (!vis[v]) {
++c;
build(v, u);
if (low[v] >= vis[u]) {
++b;
bool cont = true;
while (cont) {
instack[v = (*top--)] = 0;
cont = (v != u);
++bm, bnx[bm] = bst[v], bto[bst[v] = bm] = b;
++bm, bnx[bm] = bst[b], bto[bst[b] = bm] = v;
}
instack[(*++top) = u] = 1;
}
minimize(low[u], low[v]);
} else if (instack[v]) {
minimize(low[u], vis[v]);
}
}
}
void solve(int u, int p)
{
int i, v, d = 0;
long long x = 0;
bsz[u] = (u <= n);
for (i = bst[u]; i; i = bnx[i]) if (bto[i] != p) {
solve(v = bto[i], u), bsz[u] += bsz[v], ++d;
x += (long long) bsz[v] * (bsz[v] - 1);
}
if (u > n) {
x += (long long) (n - bsz[u]) * (n - bsz[u] - 1);
ans -= x * d;
}
}
int main()
{
int i, u, v;
scanf("%d %d", &n, &m);
for (i = 1; i <= m; ++i) {
scanf("%d %d", &u, &v);
nx[i * 2] = st[u], to[st[u] = i * 2] = v;
nx[i * 2 - 1] = st[v], to[st[v] = i * 2 - 1] = u;
}
b = n, build(1, 0);
ans = (long long) n * (n - 1) * (n - 2), solve(1, 0);
printf("%lld", ans);
}
Compilation message
count_triplets.cpp: In function 'int main()':
count_triplets.cpp:60:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &n, &m);
~~~~~^~~~~~~~~~~~~~~~~
count_triplets.cpp:62:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &u, &v);
~~~~~^~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
47 ms |
12152 KB |
Output is correct |
2 |
Correct |
48 ms |
12160 KB |
Output is correct |
3 |
Incorrect |
41 ms |
8824 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
512 KB |
Output is correct |
2 |
Correct |
5 ms |
512 KB |
Output is correct |
3 |
Correct |
5 ms |
512 KB |
Output is correct |
4 |
Correct |
5 ms |
768 KB |
Output is correct |
5 |
Correct |
5 ms |
512 KB |
Output is correct |
6 |
Correct |
5 ms |
512 KB |
Output is correct |
7 |
Correct |
5 ms |
512 KB |
Output is correct |
8 |
Correct |
5 ms |
512 KB |
Output is correct |
9 |
Correct |
5 ms |
524 KB |
Output is correct |
10 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
11 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
61 ms |
9336 KB |
Output is correct |
2 |
Correct |
55 ms |
9208 KB |
Output is correct |
3 |
Correct |
47 ms |
9336 KB |
Output is correct |
4 |
Correct |
50 ms |
9312 KB |
Output is correct |
5 |
Correct |
60 ms |
9336 KB |
Output is correct |
6 |
Correct |
65 ms |
18168 KB |
Output is correct |
7 |
Correct |
55 ms |
15356 KB |
Output is correct |
8 |
Correct |
55 ms |
13688 KB |
Output is correct |
9 |
Correct |
51 ms |
12280 KB |
Output is correct |
10 |
Incorrect |
43 ms |
7680 KB |
Output isn't correct |
11 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
384 KB |
Output is correct |
2 |
Correct |
5 ms |
512 KB |
Output is correct |
3 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
51 ms |
9336 KB |
Output is correct |
2 |
Correct |
48 ms |
9336 KB |
Output is correct |
3 |
Incorrect |
54 ms |
9464 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |