http://mendo.mk/jforum/forums/show/12.page JForum - http://www.jforum.net Internet online contest series

Over the next six months we will organize seven online contests as a warm-up for the 2021 season of high school programming competitions. Everyone is welcome to participate! Each contest will be three hours long and will feature five tasks. The contestants will also have full feedback with at most 50 submissions per task. The tasks will be of widely varying difficulty; we hope that many beginner or up-and-coming contestants will participate, as well as the more experienced ones.

The first contest will be held this Saturday, October 17, starting at 14:00 (GMT/UTC). Check out your local times at https://hsin.hr/coci/next_contest.html
You may use Python, Pascal, C/C++ or Java as your programming language of choice.
The contest will also be featured on a newly-developed judging system. If your students wish to get a bit more familiar with the system, we have uploaded the last 14 COCI seasons for them to practice on. Most problems (except for the very easy ones) have English translations.


The two relevant websites are:
https://hsin.hr/coci/ - information about the contest
https://evaluator.hsin.hr/ - judging system

We hope that you will join us or encourage your students to do so!
This is the fifteenth year in a row that we are hosting the COCI series. You can find the tasks (statements, test data and solutions) from the previous years at https://hsin.hr/coci/. There are over 600 original tasks for students to practice on!

With regards,
Kresimir Malnar
Croatian Computer Science Association]]> http://mendo.mk/jforum/posts/preList/716/3848.page http://mendo.mk/jforum/posts/preList/716/3848.page GMT
USACO will organize several online contests in 2019 and 2020. Participation is free, and open to all. The contests are available in four divisions: bronze, silver, gold, and platinum.
All returning participants start out in their former divisions, and new participants start out in the bronze division. The contests are for individuals only, not teams.

Each contest has 3 problems to which you will submit solution programs in C, C++, Pascal, Java, or Python.
The USACO 2019 December contest is available from December 13 through December 16. Visit the USACO website for more information, including the schedule for future competitions: [url]http://usaco.org/[/url]
]]> http://mendo.mk/jforum/posts/preList/712/3842.page http://mendo.mk/jforum/posts/preList/712/3842.page GMT Internet online contest series
Direct link: [url]http://hsin.hr/coci/[/url]

Over the next six months we will organize seven online contests as a warm-up for the 2020 season of high school programming competitions. Everyone is welcome to participate!
Each contest will be three hours long and will feature five tasks. The tasks will be of widely varying difficulty; we hope that many beginner or up-and-coming contestants will participate, as well as the more experienced ones.

The first contest will be held on Saturday, 19 October 2019, starting at 14:00 (GMT/UTC). You may use Python, Pascal, C/C++ or Java as your programming language of choice.

Instructions, problems and the contest system will be located at [url]http://evaluator.hsin.hr[/url]

This web page will be available for registration 48 hours before the contest.
You can find problems, test data and solutions from previous Croatian competitions in informatics here: [url]http://hsin.hr/coci/[/url]
]]> http://mendo.mk/jforum/posts/preList/711/3841.page http://mendo.mk/jforum/posts/preList/711/3841.page GMT
JOI Open Contest 2019 is an IOI-like open competition for students at
schools for secondary education. The main purpose of this contest is
to give Japanese delegations and candidates of delegations an
opportunity for training and practice. But the contest itself is open to everybody.
Everybody is welcome to attend JOI Open Contest 2019!

This year, the contest will be held on 14 July 2019.
There will be 3 tasks. Each submitted source program must be written
in C++ (C++14). Problem statements will be provided both in Japanese
and English.

The duration of the contest is 5 hours. The same contests will be held
twice (Round 1 and Round 2). Contestants can participate in one of
Round 1 or Round 2 according to their time zone. After Round 2 finishes,
we will open the judging server for one day. Interested contestants can
improve and resubmit their solutions by themselves.

After the contest finishes, we will fix the standings.
No prizes will be given to the contestants.

Contest website:
[url]https://contests.ioi-jp.org/open-2019/index.html[/url]

Contest duration: 5 hours
The number of tasks: 3 tasks
Language: English, Japanese
Programming Language: C++ (C++14)
Details will be announced on the contest website.


Date & Time:
Round 1
Sunday, July 14, 2019
13:00-18:00 +0900 (JST)
04:00-09:00 (UTC/GMT)

Round 2 (tasks for Round 1 and Round 2 are the same)
Sunday, July 14, 2019
19:00-24:00 +0900 (JST)
10:00-15:00 (UTC/GMT)

Judging Server is open until
Monday, July 15, 2019
23:00 +0900 (JST)
14:00 (UTC/GMT)

======
Executive director of the Japanese Committee for the IOI
Seiichi Tani

Chairperson of the Scientific Committee of JCIOI]]> http://mendo.mk/jforum/posts/preList/709/3839.page http://mendo.mk/jforum/posts/preList/709/3839.page GMT
Ne razbiram zosto e gresen kodov.

dp[s][k][i] e maksimalniot broj na topki sto moze da se fatat ako sme vo s-tata sekunda, mozeme da se dvizime uste k pati i vo ovaa sekunda sme na i-tata pozicija.

[code]
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ld, ld> pd;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<ld> vd;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
template <class Key, class Compare = less<Key>> // find_by_order, order_of_key
using Tree = tree<Key, null_type, Compare, rb_tree_tag, tree_order_statistics_node_update>;


int N, K, S;
int t[1001];
int dp[1001][1001][11];

void _SOLVE_() {
int T;
cin >> T;
while (T--) {
cin >> N >> K >> S;
for (int i = 1; i <= S; ++i)
cin >> t[i];
memset(dp, -1, sizeof(dp));
dp[0][K][1] = 0;
for (int s = 1; s <= S; ++s) {
for (int k = 0; k <= K; ++k) {
for (int i = 1; i <= N; ++i) {
dp[s][k][i] = dp[s-1][k][i]; //ako prethodnata sekunda stoevme ovde
if (k > 0 && k < K) {
if (i > 1)
dp[s][k][i] = max(dp[s][k][i], dp[s-1][k+1][i-1]); //ako prethodnata sekunda bevme edna pozicija levo od ovde
if (i < N)
dp[s][k][i] = max(dp[s][k][i], dp[s-1][k+1][i+1]); //ako prethodnata sekunda bevme edna pocizija desno od ovde
}
if (dp[s][k][i] != -1 && t[s] == i) //mozno e da sme ovde i topkata vo ovaa sekunda pagja kade sto sme
dp[s][k][i] += 1;
}
}
}
int ans = 0;
for (int k = 0; k <= K; ++k)
for (int i = 1; i <= N; ++i)
ans = max(ans, dp[S][k][i]);
cout << ans << endl;
}
}

int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
#ifdef _DEBUG
freopen("in.txt", "r", stdin);
freopen("out.txt", "w", stdout);
#endif
_SOLVE_();
}

[/code]

EDIT
Go smeniv redot (k > 0 && k < K) i tocno e sega. :roll:]]> http://mendo.mk/jforum/posts/preList/659/3621.page http://mendo.mk/jforum/posts/preList/659/3621.page GMT [code]#include <bits/stdc++.h>

using namespace std;

const int MAX= 1e5+10;
const int INF=(1<<30);
int N,M;
int START,END;
bool vis[MAX];
vector<pair><int,int> > graph[MAX];
struct node{
int idx;
int cost;
node(){}
node(int _idx, int _cost)
{
idx=_idx;
cost=_cost;
}

bool operator < (const node &TMP) const{
return cost > TMP.cost;

}

};

void dijkstra()
{
memset(vis,false,sizeof(vis));
priority_queue<node> q;
q.push(node(START,0));
while(!q.empty())
{
node curr=q.top();
q.pop();
if(vis[curr.idx]==false)
{
continue;
}
if(curr.idx==END)
{
cout<<curr.cost><<endl;
}
vis[curr.idx]=true;
for(int i=0; i<(int)graph[i].size(); i++)
{
int sosed=graph[curr.idx][i].first;
int val=graph[curr.idx][i].second;
if(!vis[sosed]&& curr.cost > curr.cost + val)
{
q.push(node(sosed,curr.cost + val));
}


}
}



}


int main()
{
cin>>N>>M;
for(int i=0; i<M; i++) >
{
int a,b,c;
cin>>a>>b>>c;
a--;
b--;
graph[a].push_back(make_pair(b,c));
graph[b].push_back(make_pair(a,c));
}
cin>>START>>END;
START--;
END--;
dijkstra();
return 0;
}[/code]
]]> http://mendo.mk/jforum/posts/preList/652/3584.page http://mendo.mk/jforum/posts/preList/652/3584.page GMT -----------------------------------------------------------------------------------------
Croatian Open Competition in Informatics
COCI 2018/2019
Internet online contest series


Over the next six months we will organize seven online contests
as a warm-up for the 2019 season of high school programming competitions.
Everyone is welcome to participate!

Each contest will be three hours long and will feature five tasks.
The tasks will be of widely varying difficulty; we hope that many
beginner or up-and-coming contestants will participate, as well as
the more experienced ones.

The first contest will be held on Saturday, 20 October 2018, starting
at 14:00 (GMT/UTC). Check out your local times at http://hsin.hr/coci/next_contest.html

You may use Python, Pascal, C/C++ or Java as your programming language of choice.

The two relevant websites are:
http://hsin.hr/coci/ - information about the contest
http://evaluator.hsin.hr/ - contest system

We hope that you will join us or encourage your students to do so!]]> http://mendo.mk/jforum/posts/preList/642/3551.page http://mendo.mk/jforum/posts/preList/642/3551.page GMT http://mendo.mk/jforum/posts/preList/524/3289.page http://mendo.mk/jforum/posts/preList/524/3289.page GMT http://mendo.mk/algoritmi/Task.do?competition=150&id=255.

Nemie jasna zosto pominuva so greedy resenie a so DP(dinamicko programiranje) resenie ne pominuva.

Ova e resenieto za koe pominuva

[code]#include <iostream>
#include <algorithm>
#include <cmath>

using namespace std;

int main() {

int n;

cin >> n;

int a[n];

for (int i = 0 ; i < n ; i++){
cin >> a[i];
}

sort(a, a + n);

int sum1 = a[n - 1] , sum2 = a[n - 2];



for (int i = n - 3 ; i >= 0 ; i--){
if (sum1 < sum2){
sum1 += a[i];
}else {
sum2 += a[i];
}
}

cout << min(sum1, sum2) << " " << max(sum1, sum2) << endl;

return 0;
}[/code]

a ova e resenieto kade sto pagja na runtime
[code]#include <iostream>
#include <algorithm>
#include <cmath>
#include <climits>

using namespace std;

int findMin(int arr[], int n, int sum){

bool dp[n + 1][sum + 1];

for (int i = 0; i <= n; i++)
dp[i][0] = true;

for (int i = 1; i <= sum; i++)
dp[0][i] = false;

for (int i = 1; i <= n; i++){
for (int j = 1; j <= sum; j++){

dp[i][j] = dp[i - 1][j];

if (arr[i - 1] <= j)
dp[i][j] |= dp[i - 1][j - arr[i - 1]];
}
}

int diff = INT_MAX;

for (int j = sum / 2; j >= 0; j--){

if (dp[n][j]){
diff = sum - 2 * j;
break;
}
}

return diff;
}

int main() {

int n, sum = 0;

cin >> n;

int a[n];

for (int i = 0 ; i < n ; i++){
cin >> a[i];
sum += a[i];
}

int minVal = findMin(a, n, sum);

int large = (sum + minVal) / 2;
int small = large - minVal;

cout << small << " " << large << endl;

return 0;
}[/code]

Prasanjeto mi bese zosto zadacata e napravena samo da se resava so greedy approach a ne kako sto treba.
Ova go sogledav koga vidov deka vo zadacata pisuva da se najdi optimalnoto resenie kade sto ke ima minimalna razlika pomegju dvete grupi od nakiti no za dolniot slucaj ako odime po greedy resenieto(za koe pominuva 10/10) ke bide
14 12 10 20 22 ====> greedy (22 + 12 + 10 = 44 i 20 + 14 = 34 sto ke ispecati (34 44) no treba da bide (10 + 12 + 14 = 36 20 + 22 = 42 ) sto znaci pagja na ovoj slucaj no 10/10 pominuva na od MENDO slucaite sto ne mie jasno ....)
dodeka so DP resenieto si pecati najoptimalnoto grupiranje (36 42) no pagja na runtime za 4 slucai sto ne mie jasno zosto vaka e postavena zadacata.]]> http://mendo.mk/jforum/posts/preList/492/3191.page http://mendo.mk/jforum/posts/preList/492/3191.page GMT http://codeit.bg/eng.
Учествувајте!]]> http://mendo.mk/jforum/posts/preList/444/3004.page http://mendo.mk/jforum/posts/preList/444/3004.page GMT http://mendo.mk/jforum/posts/preList/432/2967.page http://mendo.mk/jforum/posts/preList/432/2967.page GMT
Имам прашање за задачата „Бакшиш„ (http://mendo.mk/Task.do?id=528).

Имено, во еден од тест примерите: сметка 1900, кеш на располагање 1000000, вашиот резултат изнесува 23, додека мојот е 20.

Ве молам да ми појасните кои се тие 23, кога 1900+5% = 1995; 1900+10% = 2090; Во овој опсег има само 20 вредности деливи со 5:

1. 1995
2. 2000
3. 2005
4. 2010
5. 2015
6. 2020
7. 2025
8. 2030
9. 2035
10. 2040
11. 2045
12. 2050
13. 2055
14. 2060
15. 2065
16. 2070
17. 2075
18. 2080
19. 2085
20. 2090]]> http://mendo.mk/jforum/posts/preList/377/2802.page http://mendo.mk/jforum/posts/preList/377/2802.page GMT
The tasks will be exactly the ones used during the real competition and will be graded using the same test data. Everybody is welcome and we are happy to invite you and all your friends/colleagues/students to participate!

1st Competition Day ... Tuesday, October 15, 14:00-19:00 GMT/UTC
2nd Competition Day ... Thursday, October 17, 14:00-19:00 GMT/UTC

There will be three tasks on each day of competition. The tasks will be algorithmic in nature and reasonably hard to solve. You may use Pascal, C or C++ as your programming language of choice.

You can find details about the contest at http://hsin.hr/ceoi2013/index.php?page=online_contest
]]> http://mendo.mk/jforum/posts/preList/321/2597.page http://mendo.mk/jforum/posts/preList/321/2597.page GMT COCI 2013/2014
Internet online contest series


Over the next seven months we are planning to organize seven online contests
as a warm-up for the 2014 season of high school programming competitions.
Everyone is welcome to participate!

Each contest will be three hours long and will feature six tasks.
The tasks will be of widely varying difficulty; we are hoping to have many
beginner or up-and-coming contestants participate, as well as those
more experienced.

The first contest will be held on Saturday, 28th September 2013, starting
at 14:00 (GMT/UTC). Check out your local times at [url]http://hsin.hr/coci/next_contest.html[/url].

You may use Pascal, C/C++ or Java as your programming language of choice.

The two relevant websites are:
http://hsin.hr/coci/ - information about the contest
http://evaluator.hsin.hr/ - contest system

We hope that you will join us or encourage your students to do so!

This is the eighth year in a row that we are hosting the COCI series. You
can find tasks (statements, test data and solutions) from the previous
seven years at [url]http://hsin.hr/coci/[/url]. That is over 300 original tasks for
students to practice on!


Project Manager
-------
Kresimir Malnar
Croatian Computer Science Association]]> http://mendo.mk/jforum/posts/preList/319/2595.page http://mendo.mk/jforum/posts/preList/319/2595.page GMT Можете да ги најдете тука: [url]http://mendo.mk/Training.do?cid=1[/url]]]> http://mendo.mk/jforum/posts/preList/318/2592.page http://mendo.mk/jforum/posts/preList/318/2592.page GMT