#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vi = vector<int>;
using vl = vector<ll>;
#define pb push_back
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define lb lower_bound
#define ub upper_bound
using pi = pair<int,int>;
#define f first
#define s second
#define mp make_pair
namespace output {
void pr(int x) {
cout << x;
}
void pr(long x) {
cout << x;
}
void pr(ll x) {
cout << x;
}
void pr(unsigned x) {
cout << x;
}
void pr(unsigned long x) {
cout << x;
}
void pr(unsigned long long x) {
cout << x;
}
void pr(float x) {
cout << x;
}
void pr(double x) {
cout << x;
}
void pr(long double x) {
cout << x;
}
void pr(char x) {
cout << x;
}
void pr(const char * x) {
cout << x;
}
void pr(const string & x) {
cout << x;
}
void pr(bool x) {
pr(x ? "true" : "false");
}
template < class T1, class T2 > void pr(const pair < T1, T2 > & x);
template < class T > void pr(const T & x);
template < class T, class...Ts > void pr(const T & t,
const Ts & ...ts) {
pr(t);
pr(ts...);
}
template < class T1, class T2 > void pr(const pair < T1, T2 > & x) {
pr("{", x.f, ", ", x.s, "}");
}
template < class T > void pr(const T & x) {
pr("{"); // const iterator needed for vector<bool>
bool fst = 1;
for (const auto & a: x) pr(!fst ? ", " : "", a), fst = 0;
pr("}");
}
void ps() {
pr("\n");
} // print w/ spaces
template < class T, class...Ts > void ps(const T & t,
const Ts & ...ts) {
pr(t);
if (sizeof...(ts)) pr(" ");
ps(ts...);
}
void pc() {
cout << "]" << endl;
} // debug w/ commas
template < class T, class...Ts > void pc(const T & t,
const Ts & ...ts) {
pr(t);
if (sizeof...(ts)) pr(", ");
pc(ts...);
}
#define dbg(x...) pr("[", #x, "] = ["), pc(x);
}
#ifdef mikey
using namespace output;
#else
using namespace output;
#define dbg(x...)
#endif
const int MX = 10005;
const int MOD = (int) (1e6 + 7);
const ll INF = (ll) 1e18;
ll dp[2][MX];
int main(){
#ifdef mikey
freopen("a.in", "r", stdin);
#endif
ios::sync_with_stdio(false);
cin.tie(0);
int n; cin >> n;
ll ans = 0;
vl a(n);
vl pref(n);
for (int i = 0; i < n; i++) {
cin >> a[i];
pref[i] = a[i];
if (i) pref[i] = max(pref[i], pref[i - 1]);
}
for (int i = 1; i <= n; i++) dp[0][i] = 1;
for (int i = 1; i < n; i++) {
for (int j = 1; j < n; j++) {
dp[i & 1][j] = (dp[(i & 1) ^ 1][j] * j) % MOD;
while (dp[i & 1][j] > MOD) dp[i & 1][j] -= MOD;
dp[i & 1][j] += dp[(i & 1) ^ 1][j + 1];
while (dp[i & 1][j] > MOD) dp[i & 1][j] -= MOD;
}
int pos = n - (i + 1);
ans = (ans + ((ll) (a[pos] - 1) * dp[i & 1][(pos == 0 ? 0 : pref[pos - 1])]) % MOD) % MOD;
}
cout << (ans + 1) % MOD << '\n';
}
Compilation message
teams.cpp:104: warning: "dbg" redefined
104 | #define dbg(x...)
|
teams.cpp:97: note: this is the location of the previous definition
97 | #define dbg(x...) pr("[", #x, "] = ["), pc(x);
|
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
364 KB |
Output is correct |
2 |
Incorrect |
0 ms |
364 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
364 KB |
Output is correct |
2 |
Incorrect |
0 ms |
364 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
0 ms |
364 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
364 KB |
Output isn't correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
364 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
3 ms |
364 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
11 ms |
364 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
938 ms |
748 KB |
Output isn't correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
243 ms |
512 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
945 ms |
748 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |