#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define conts continue
#define sz(a) (int)a.size()
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define ceil2(x,y) ((x+y-1)/(y))
#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)
template<typename T>
void amin(T &x, T y){
x = min(x,y);
}
template<typename T>
void amax(T &x, T y){
x = max(x,y);
}
template<typename A,typename B>
string to_string(pair<A,B> p);
string to_string(const string &s){
return "'"+s+"'";
}
string to_string(const char* s){
return to_string((string)s);
}
string to_string(bool b){
return b?"true":"false";
}
template<typename A>
string to_string(A v){
string res = "{";
trav(x,v){
res += to_string(x)+",";
}
if(res.back() == ',') res.pop_back();
res += "}";
return res;
}
template<typename A,typename B>
string to_string(pair<A,B> p){
return "("+to_string(p.ff)+","+to_string(p.ss)+")";
}
#define debug(x) cout << "[" << #x << "]: "; cout << to_string(x) << endl
/*
refs:
edi
*/
const int MOD = 1e9 + 7;
const int NN = 1e5 + 5;
const int inf1 = 1e9 + 5;
const ll inf2 = (ll)1e18 + 5;
bool dbg = false;
/// You may use:
// The number of students
int N;
// The probability any given student is positive
double P;
// This function performs a test on a subset of samples.
// Its argument is a vector of Booleans of length N,
// where the i-th element is true if the i-th sample should be added to the mix.
// It returns true if (and only if) at least one of the samples in the mix is positive.
bool test_students(std::vector<bool> mask) {
if(dbg) return 'P';
assert(mask.size() == (size_t)N);
std::string mask_str(N, ' ');
for (int i = 0; i < N; i++)
mask_str[i] = mask[i] ? '1' : '0';
printf("Q %s\n", mask_str.c_str());
fflush(stdout);
char answer;
scanf(" %c", &answer);
return answer == 'P';
}
/// You should implement:
// This function will be called once for each test instance.
// It should use test_students to determine which samples are positive.
// It must return a vector of Booleans of length N,
// where the i-th element is true if and only if the i-th sample is positive.
std::vector<bool> find_positive() {
// std::vector<bool> answer(N);
// return answer;
int n = N;
// vector<ld> dp(n+5,inf2);
// vector<ll> par(n+5,-1);
// dp[0] = dp[1] = 0;
// for(int i = 2; i <= n; ++i){
// for(int j = 1; j < i; j++){
// ld all_neg2 = powl((ld)1-P,i-j);
// ld all_neg = powl((ld)1-P,j) * (1 - all_neg2);
// ld val = 1+all_neg*dp[i-j];
// val += (1-all_neg)*(dp[j]+1+(1-all_neg2)*dp[i-j]);
// if(val < dp[i]){
// dp[i] = val;
// par[i] = j;
// }
// }
// // std::cout << "at N = " << i << " got ev " << dp[i] << " and par is " << par[i] << '\n';
// }
// return vector<bool>(n);
// for(int i = 2; i <= n; ++i){
// rep1(j,i-1){
// ld all_neg = pow((ld)1-P,j);
// ld val = 1+all_neg*dp[i-j];
// ld all_neg2 = pow((ld)1-P,i-j);
// val += (1-all_neg)*(dp[j]+1+(1-all_neg2)*dp[i-j]);
// if(val < dp[i]){
// dp[i] = val;
// par[i] = j;
// }
// }
// }
// vector<bool> ans(n);
// return ans;
vector<bool> ans(n);
if(P > 0.25){
rep(i,n){
vector<bool> mask(n);
mask[i] = 1;
ans[i] = test_students(mask);
}
return ans;
}
vector<int> pos(n);
iota(all(pos),0);
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
shuffle(all(pos),rng);
auto go = [&](int l, int r, auto &&go){
if(l > r) return;
vector<bool> mask(n);
for(int i = l; i <= r; ++i){
mask[pos[i]] = 1;
}
int len = r-l+1;
if(len != n){
if(!test_students(mask)) return;
}
if(l == r){
ans[pos[l]] = 1;
return;
}
if(len == 2){
mask[pos[r]] = 0;
if(!test_students(mask)){
ans[pos[r]] = 1;
}
else{
ans[pos[l]] = 1;
mask[pos[l]] = 0, mask[pos[r]] = 1;
if(test_students(mask)){
ans[pos[r]] = 1;
}
}
return;
}
int block_cnt = min(len,3);
int s1 = len/block_cnt, s2 = ceil2(len,block_cnt);
int c1 = block_cnt, c2 = len%block_cnt;
c1 -= c2;
int pos = l;
vector<pii> nxt;
rep1(iter,block_cnt){
if(iter <= c1){
nxt.pb({pos,pos+s1-1});
pos += s1;
}
else{
nxt.pb({pos,pos+s2-1});
pos += s2;
}
}
assert(pos == r+1);
for(auto [lx,rx] : nxt){
go(lx,rx,go);
}
};
double eps = 1e-6;
int B = 0;
if(abs(P-0.001) <= eps){
B = n;
}
else if(abs(P-0.005256) <= eps){
B = 150;
}
else if(abs(P-0.011546) <= eps){
B = 60;
}
else if(abs(P-0.028545) <= eps){
B = 20;
}
else if(abs(P-0.039856) <= eps){
B = 16;
}
else if(abs(P-0.068648) <= eps){
B = 8;
}
else if(abs(P-0.104571) <= eps){
B = 8;
}
else{
B = 4;
}
auto first_one = [&](int l, int r, auto &&first_one) -> int{
if(l == r) return l;
int mid = (l+r) >> 1;
vector<bool> mask(n);
for(int i = l; i <= mid; ++i){
mask[pos[i]] = 1;
}
if(test_students(mask)){
return first_one(l,mid,first_one);
}
else{
return first_one(mid+1,r,first_one);
}
};
for(int i = 0; i < n; ){
vector<bool> mask(n);
int r = min(i+B-1,n-1);
for(int x = i; x <= r; ++x){
mask[pos[x]] = 1;
}
if(!test_students(mask)){
i = r+1;
conts;
}
int j = first_one(i,r,first_one);
ans[pos[j]] = 1;
i = j+1;
}
return ans;
}
int main() {
#ifdef LOCAL
dbg = true;
#endif
int T;
scanf("%d %lf %d", &N, &P, &T);
// You may perform any extra initialization here.
for (int i = 0; i < T; i++) {
std::vector<bool> answer = find_positive();
assert(answer.size() == (size_t)N);
std::string answer_str(N, ' ');
for (int j = 0; j < N; j++)
answer_str[j] = answer[j] ? '1' : '0';
printf("A %s\n", answer_str.c_str());
fflush(stdout);
char verdict;
scanf(" %c", &verdict);
if (verdict == 'W')
exit(0);
}
return 0;
}
Compilation message
Main.cpp: In function 'std::vector<bool> find_positive()':
Main.cpp:174:10: warning: variable 'go' set but not used [-Wunused-but-set-variable]
174 | auto go = [&](int l, int r, auto &&go){
| ^~
Main.cpp: In function 'bool test_students(std::vector<bool>)':
Main.cpp:107:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
107 | scanf(" %c", &answer);
| ~~~~~^~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:305:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
305 | scanf("%d %lf %d", &N, &P, &T);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:321:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
321 | scanf(" %c", &verdict);
| ~~~~~^~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
344 KB |
Output is correct |
2 |
Correct |
6 ms |
344 KB |
Output is correct |
3 |
Correct |
6 ms |
344 KB |
Output is correct |
4 |
Correct |
8 ms |
344 KB |
Output is correct |
5 |
Correct |
6 ms |
344 KB |
Output is correct |
6 |
Correct |
6 ms |
344 KB |
Output is correct |
7 |
Correct |
8 ms |
344 KB |
Output is correct |
8 |
Correct |
8 ms |
344 KB |
Output is correct |
9 |
Correct |
6 ms |
344 KB |
Output is correct |
10 |
Correct |
6 ms |
344 KB |
Output is correct |
11 |
Correct |
6 ms |
344 KB |
Output is correct |
12 |
Correct |
8 ms |
344 KB |
Output is correct |
13 |
Correct |
6 ms |
344 KB |
Output is correct |
14 |
Correct |
6 ms |
344 KB |
Output is correct |
15 |
Correct |
6 ms |
344 KB |
Output is correct |
16 |
Correct |
6 ms |
344 KB |
Output is correct |
17 |
Correct |
3 ms |
344 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
34 ms |
344 KB |
Output is correct (P=0.001, F=15.1, Q=10.8) -> 90.00 points |
2 |
Correct |
111 ms |
344 KB |
Output is correct (P=0.005256, F=51.1, Q=46.9) -> 90.00 points |
3 |
Correct |
214 ms |
344 KB |
Output is correct (P=0.011546, F=94.9, Q=91.0) -> 90.00 points |
4 |
Correct |
463 ms |
344 KB |
Output is correct (P=0.028545, F=191.5, Q=191.0) -> 90.00 points |
5 |
Correct |
603 ms |
344 KB |
Output is correct (P=0.039856, F=246.3, Q=243.9) -> 90.00 points |
6 |
Correct |
883 ms |
344 KB |
Output is correct (P=0.068648, F=366.2, Q=366.0) -> 90.00 points |
7 |
Correct |
1243 ms |
344 KB |
Output is correct (P=0.104571, F=490.3, Q=493.4) -> 87.78 points |
8 |
Correct |
1548 ms |
344 KB |
Output is correct (P=0.158765, F=639.1, Q=632.7) -> 90.00 points |
9 |
Correct |
1851 ms |
344 KB |
Output is correct (P=0.2, F=731.4, Q=741.0) -> 85.51 points |