#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int MAXN = 1e5 + 10;
#define debug(...) fprintf(stderr, __VA_ARGS__)
//#define debug(...)
#define fi first
#define se second
#define all(v) (v).begin(), (v).end()
#define fillchar(a, s) memset((a), (s), sizeof(a))
ll sqr (ll x) {
return x * x;
}
struct union_find {
int par[MAXN];
int sz[MAXN];
union_find() {
for (int i = 0; i < MAXN; i++) {
par[i] = i;
sz[i] = 1;
}
}
int find (int x) {
return x == par[x] ? x : par[x] = find(par[x]);
}
void merge (int x, int y) {
x = find(x);
y = find(y);
if (x == y) {
return;
}
par[x] = y;
sz[y] += sz[x];
}
};
int N, M;
vector<int> adj[MAXN];
vector<int> verts;
int par[MAXN], depth[MAXN];
bool vis[MAXN];
union_find uf = union_find();
union_find cy = union_find(); //cycle components
void dfs (int x, int p) {
debug("x = %d\n", x);
verts.push_back(x);
vis[x] = true;
par[x] = p;
for (int y : adj[x]) {
if (y != p) {
if (vis[y]) {
if (depth[y] < depth[x]) {
//then it's a component
for (int i = x; ; i = par[i]) {
cy.merge(x, i);
debug("merge(%d, %d)\n", x, i);
if (i == y) {
break;
}
}
}
} else {
depth[y] = depth[x] + 1;
dfs(y, x);
}
}
}
}
vector<int> cadj[MAXN]; //comp adjacent
int cpar[MAXN];
int sub[MAXN];
vector<int> cverts;
vector<int> cyv[MAXN];
void dfsc (int x) {
cverts.push_back(x);
sub[x] = cy.sz[x];
for (int y : cadj[x]) {
cpar[y] = x;
cadj[y].erase(find(all(cadj[y]), x));
dfsc(y);
sub[x] += sub[y];
}
}
ll go (int root) {
dfs(root, 0);
for (int x : verts) {
int fx = cy.find(x);
cyv[fx].push_back(x);
for (int y : adj[x]) {
int fy = cy.find(y);
if (fx != fy) {
cadj[fx].push_back(fy);
debug("CADJ %d %d\n", fx, fy);
}
}
}
int szroot = uf.sz[root];
int froot = cy.find(root);
dfsc(froot);
//ok let's consider when the stuff is good!
ll ans = 0;
debug("WE HAVE szroot = %d\n", szroot);
for (int c : cverts) {
debug("--------COMPONENT OF %d----------------\n", c);
//all 3 are in the same component
ll s = cy.sz[c];
ans += s * (s - 1) * (s - 2);
debug("s = %lld\n", s);
//all 3 are in different component. c is the transition.
//also have to count individual ones
ll pans = ans;
ll totsb = 0;
ll ncho2 = 0;
for (int x : cyv[c]) {
ll sumsb = 0;
for (int y : adj[x]) {
int fy = cy.find(y);
if (c != fy) {
ll sb;
if (fy == cpar[c]) {
sb = szroot - sub[c];
} else {
sb = sub[fy];
}
ans -= sqr(sb);
sumsb += sb;
}
}
ans += sqr(sumsb);
ncho2 -= sqr(sumsb);
totsb += sumsb;
}
assert(totsb == szroot - s);
ncho2 += sqr(totsb);
ans += ncho2 * s;
debug("all3indiff = %lld\n", ans - pans);
//the stuff right below this comment is actually wrong.
/*
//two of them are in this component. one of them is in different component
debug("s = %lld. szroot = %d. So we add %lld\n", s, szroot, 2 * s * (s - 1) * (szroot - s));
ans += 2 * s * (s - 1) * (szroot - s); //ans += 4 * C(s, 2) * (szroot - s)
*/
//ok now this may be correct...
ans += 2 * s * (s - 1) * (szroot - s); //ans += 4 * C(s, 2) * (szroot - s)
ans -= 2 * (s - 1) * (szroot - s);
}
#warning RESET AT THE END!
verts.clear();
cverts.clear();
return ans;
}
namespace brute_force {
bool adj[10][10];
bool dp[1 << 10][10];
vector<int> gmsk[1 << 10];
bool can[10][10][10];
int brute() {
//can we try to go from here
for (int i = 0; i < M; i++) {
int x, y;
scanf("%d %d", &x, &y);
x--;
y--;
adj[x][y] = adj[y][x] = true;
}
for (int c = 0; c < N; c++) {
for (int i = 0; i < (1 << N); i++) {
gmsk[i].clear();
}
fillchar(dp, 0);
for (int i = 0; i < (1 << N); i++) {
for (int j = 0; j < (1 << N); j++) {
if ((i & j) == (1 << c)) {
gmsk[i].push_back(j);
}
}
}
dp[1 << c][c] = true;
for (int i = 0; i < (1 << N); i++) {
for (int j = 0; j < N; j++) {
if (dp[i][j]) {
//then try to go to a new one
for (int k = 0; k < N; k++) {
if (!(i & (1 << k)) && adj[j][k]) {
dp[i ^ (1 << k)][k] = true;
}
}
}
}
}
for (int i = 0; i < N; i++) {
if (i != c) {
for (int j = 0; j < N; j++) {
if (j != i && j != c) {
//then see if you can go there
for (int k = 0; k < (1 << N); k++) {
if (dp[k][i]) {
for (int m : gmsk[k]) {
if (dp[m][j]) {
can[i][c][j] = true;
}
}
}
}
}
}
}
}
}
int ans = 0;
for (int i = 0; i < N; i++) {
for (int j = 0; j < N; j++) {
for (int k = 0; k < N; k++) {
if (i != j && j != k && k != i) {
ans += can[i][j][k];
}
}
}
}
return ans;
}
}
int main() {
scanf("%d %d", &N, &M);
if (N <= 10) {
//printf("%d\n", brute_force::brute());
//return 0;
}
for (int i = 1; i <= M; i++) {
int x, y;
scanf("%d %d", &x, &y);
adj[x].push_back(y);
adj[y].push_back(x);
uf.merge(x, y);
}
ll ans = 0;
for (int i = 1; i <= N; i++) {
if (i == uf.find(i)) {
ans += go(i);
}
}
printf("%lld\n", ans);
}
Compilation message
count_triplets.cpp:168:2: warning: #warning RESET AT THE END! [-Wcpp]
#warning RESET AT THE END!
^~~~~~~
count_triplets.cpp: In function 'int brute_force::brute()':
count_triplets.cpp:184:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &x, &y);
~~~~~^~~~~~~~~~~~~~~~~
count_triplets.cpp: In function 'int main()':
count_triplets.cpp:253:7: 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:260:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &x, &y);
~~~~~^~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
8952 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
8952 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
549 ms |
29836 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
23 ms |
29836 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1080 ms |
29836 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
23 ms |
29836 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1077 ms |
29836 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
8952 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
8952 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
