| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 97432 | jasony123123 | Calvinball championship (CEOI15_teams) | C++11 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
#include <array>
//#include <ext/pb_ds/tree_policy.hpp>
//#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
//using namespace __gnu_pbds;
#define FOR(i,start,end) for(int i=start;i<(int)(end);i++)
#define FORE(i,start,end) for(int i=start;i<=(int)end;i++)
#define RFOR(i,start,end) for(int i = start; i>end; i--)
#define RFORE(i,start,end) for(int i = start; i>=end; i--)
#define all(a) a.begin(), a.end()
#define mt make_tuple
#define mp make_pair
#define v vector
#define sf scanf
#define pf printf
#define dvar(x) cout << #x << " := " << x << "\n"
#define darr(x,n) FOR(i,0,n) cout << #x << "[" << i << "]" << " := " << x[i] << "\n"
typedef long long ll;
typedef long double ld;
typedef pair<int, int > pii;
typedef pair<ll, ll> pll;
//template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T> void minn(T &a, T b) { a = min(a, b); }
template<class T> void maxx(T &a, T b) { a = max(a, b); }
void io() {
#ifdef LOCAL_PROJECT
freopen("input.in", "r", stdin); freopen("output.out", "w", stdout);
#else
#endif
ios_base::sync_with_stdio(false); cin.tie(NULL);
}
const ll INF = 1e14;
/***********************CEOI 2015 D1 Calvin*****************************************/
const int MOD = 1000007a;
inline int add(int a, int b) { return (a + b) % MOD; }
inline int mul(int a, int b) { return (1LL * a*b) % MOD; }
int n, nums[10000], seen[10000];
array<int, 10000> dpold, dpcur;
int main() {
io();
cin >> n;
FOR(i, 0, n) cin >> nums[i];
seen[0] = nums[0];
FOR(i, 1, n) seen[i] = max(nums[i], seen[i - 1]);
int ans = 1;
RFORE(i, n - 1, 0) {
if (n - 1 - i == 0)
fill(all(dpcur), 1);
else {
swap(dpold, dpcur);
FOR(s, 1, n)
dpcur[s] = add(mul(s, dpold[s]), dpold[s + 1]);
}
ans = add(ans, mul(nums[i] - 1, dpcur[seen[i - 1]]));
}
cout << ans << "\n";
}