# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
430111 | dreezy | Counting Mushrooms (IOI20_mushrooms) | C++17 | 1092 ms | 1566712 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 "mushrooms.h"
using namespace std;
#define pb push_back
#define mp make_pair
vector<vector<int>> queries;
int use(int l, int r){
if(queries[l][r]!= -1) return queries[l][r];
vector<int> q;
if(l != 0)
for(int i =l; i<=r; i++) q.pb(i);
else
q.pb(0), q.pb(r);
int res = use_machine(q);
queries[l][r] = res;
return res;
}
int geta(int l, int r){
if( l > r) return 0;
if(l == r)
return use(0,l) == 0;
vector<int> inds;
int res = use(l, r);
if(res == 0){
if(use(0,l)== 0)
return r - l + 1;
else
return 0;
}
else if(res == r -l){
if((r - l + 1)%2 == 0) return (r - l + 1)/2;
else {
if(use(0,l) == 0){
return (r - l + 1)/2 + 1;
}
else
return (r - l + 1)/2;
}
}
else if(res == 1){
int lo = l;
int hi = r;
int target = !use(0,lo);
while(lo!= hi){
int mi = (lo + hi)/2;
if( use(0,mi) == target){
hi = mi;
}
else{
lo = mi + 1;
}
}
if(target == 1){//we were looking for the first B
//cout << l <<", "<<r <<": "<<lo<<endl;
return lo - l;
}
else{//we were looking for the first A
return r - lo + 1;
}
}
int mid = (l + r)/2;
return geta( l, mid) + geta(mid + 1, r);
}
int count_mushrooms(int n) {
queries.assign(n, vector<int>(n, -1));
int ans = 1;
int blcksz =25;
for(int block = 1; block <n; block += blcksz){
ans += geta(block, min(blcksz + block -1 , n -1) );
}
return ans;
}
# | Verdict | Execution time | Memory | Grader output |
---|---|---|---|---|
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