| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 1045506 |
2024-08-06T04:24:12 Z |
Requiem |
Sails (IOI07_sails) |
C++17 |
|
517 ms |
5468 KB |
#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#define MOD 1000000007
#define inf 1e18
#define fi first
#define se second
#define endl "\n"
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORD(i,a,b) for(int i=a;i>=b;i--)
#define sz(a) ((int)(a).size())
#define pi 3.14159265359
#define TASKNAME "sails"
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return true; }; return false; }
using namespace std;
typedef pair<int,int> ii;
typedef pair<int,ii> iii;
typedef vector<int> vi;
const int MAXN = 1e5 + 9;
struct Poles{ //cây cột chứa các sail
int height, numSail;
} P[MAXN];
int n;
void input(){
cin >> n;
for(int i = 1; i <= n; i++){
cin >> P[i].height >> P[i].numSail;
}
}
namespace subtask1{
bool check(){
return n <= 200;
}
vector<int> state[MAXN];
int ans = inf;
map<int, int> cnt;
int calc(){
cnt.clear();
int sum = 0;
for(int i = n; i >= 1; i--){
for(auto x: state[i]){
sum += cnt[x];
cnt[x]++;
}
}
return sum;
}
void backtrack(int pos, int numChosen, int last){
if (pos == n + 1){
minimize(ans, calc());
return;
}
if (numChosen < P[pos].numSail){
for(int j = last + 1; j <= P[pos].height; j++){
state[pos].pb(j);
backtrack(pos, numChosen + 1, j);
state[pos].pop_back();
}
}
else{
backtrack(pos + 1, 0, 0);
}
}
void solve(){
backtrack(1, 0, 0);
cout << ans << endl;
}
}
/**
* IOI 2007 Sail Solution:
* bài này mình đang suy nghĩ đến việc tham lam.
* Với 1 thằng, ta sẽ cố chọn những thằng cao nhất có thể chưa được chọn vì nó là tốt nhất
* Xét đến vị trí i, liệu kết quả của ta có xuất phát từ vị trí i + 1 hay không.
*
* Ưu tiên số 1: Rải đều ra.
* ƯU tiên số 2: chọn càng cao càng tốt.
*
*
*/
namespace subtask2{
bool check(){
return n <= 2000;
}
int cnt[2002];
ii temp[2002];
bool custom_cmp(ii a, ii b){
return (a.fi == b.fi) ? (a.se > b.se) : (a.fi < b.fi);
}
void solve(){
int ans1 = 0;
memset(cnt, 0, sizeof(cnt));
for(int i = n; i >= 1; i--){
for(int j = P[i].height; j >= 1; j--){
temp[j] = {cnt[j], j};
}
sort(temp + 1, temp + 1 + P[i].height, custom_cmp);
for(int j = 1; j <= P[i].numSail; j++){
ans1 += temp[j].fi;
cnt[temp[j].se]++;
}
}
int ans2 = 0;
memset(cnt, 0, sizeof(cnt));
for(int i = 1; i <= n; i++){
for(int j = P[i].height; j >= 1; j--){
temp[j] = {cnt[j], j};
}
sort(temp + 1, temp + 1 + P[i].height, custom_cmp);
for(int j = 1; j <= P[i].numSail; j++){
ans2 += temp[j].fi;
cnt[temp[j].se]++;
}
}
cout << min(ans1, ans2) << endl;
}
}
void solve(){
// if (subtask1::check()) return subtask1::solve();
if (subtask2::check()) return subtask2::solve();
}
main()
{
fast;
if (fopen(TASKNAME".inp","r")){
freopen(TASKNAME".inp","r",stdin);
freopen(TASKNAME".out","w",stdout);
}
input();
solve();
}
/**
Warning:
- MLE / TLE?
- Gioi han mang?
- Gia tri max phai luon gan cho -INF
- long long co can thiet khong?
- tran mang.
- code can than hon
**/
Compilation message
sails.cpp:136:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
136 | main()
| ^~~~
sails.cpp: In function 'int main()':
sails.cpp:140:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
140 | freopen(TASKNAME".inp","r",stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
sails.cpp:141:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
141 | freopen(TASKNAME".out","w",stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
2652 KB |
Output is correct |
| 2 |
Correct |
1 ms |
2652 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
2652 KB |
Output is correct |
| 2 |
Correct |
0 ms |
2652 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
2652 KB |
Output is correct |
| 2 |
Correct |
0 ms |
2652 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
2652 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
517 ms |
5460 KB |
Execution killed with signal 11 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
2904 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
3420 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
3932 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
4700 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
5212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
10 ms |
5468 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
