# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
941640 | shoryu386 | A Difficult(y) Choice (BOI21_books) | C++17 | 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.
#include <bits/stdc++.h>
#include "books.h"
using namespace std;
typedef long long ll;
long long gA, gK;
void recur(int x, int taken, ll sum, vector<pair<int, ll>> takeitem, vector<pair<int, ll>> &items){
if (taken == gK){
if (gA <= sum && sum <= 2LL*gA){
vector<int> indices;
for (int x = 0; x < (int)takeitem.size(); x++){
indices.push_back(t[x].first);
}
answer(indices);
return;
}
return;
}
#include <bits/stdc++.h>
#include "books.h"
using namespace std;
typedef long long ll;
long long gA, gK;
void recur(int x, int taken, ll sum, vector<pair<int, ll>> takeitem, vector<pair<int, ll>> &items){
if (taken == gK){
if (gA <= sum && sum <= 2LL*gA){
vector<int> indices;
for (int x = 0; x < (int)takeitem.size(); x++){
indices.push_back(t[x].first);
}
answer(indices);
return;
}
return;
}
if (x == items.size()) return;
recur(x+1, taken, sum, takeitem, items);
if (taken != gK){
takeitem.push_back(items[x]);
recur(x+1, taken+1, sum+items[x].second, takeitem, items);
}
}
void solve(int N, int K, long long A, int S) {
// TODO implement this function
//k books, sum of A
//x, x+1, x+2, x+3, x+4, x+5... and so on
gA = A; gK = K;
int extrasum = 0;
for (int x = 0; x < K; x++){
extrasum += x;
}
//we want A <= x*K + extrasum <= 2*A
//x*K + extrasum >= A
//x*K >= A-extrasum
//x >= (A-extrasum)/K
ll target = (A - extrasum)/K + ((A - extrasum)%K != 0);
//to do: check rounding
if (A - extrasum <= 0) {impossible(); return;}
int l = 1, r = N+1-K, ans = N+1-K;
while (l <= r){
int m = (l+r)/2;
ll res = skim(m);
if (res >= target){
r = m-1;
ans = m;
}
else{
l = m+1;
}
}
vector<pair<int, ll>> items; set<int> indicesInside;
for (int x = max(1, ans-10); x < min(N+1, ans+K); x++){
items.push_back({x, skim(x)}); indicesInside.insert(x);
}
for (int x = 1; x <= 10; x++){
if (indicesInside.count(x) == 0) items.push_back({x, skim(x)}), indicesInside.insert(x);
}
recur(0, 0, 0, {}, items);
impossible();
}