CSES - Putka Open 2020 – 2/5 - Results
Submission details
Task:Torni
Sender:mango_lassi
Submission time:2020-09-27 21:04:37 +0300
Language:C++ (C++11)
Status:READY
Result:0
Feedback
groupverdictscore
#10
#20
#30
Test results
testverdicttimegroup
#10.01 s1, 2, 3details
#20.04 s2, 3details
#30.04 s3details

Compiler report

input/code.cpp: In function 'std::vector<long long int> test(ll, std::vector<long long int>)':
input/code.cpp:12:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int i = 1; i < as.size(); ++i) {
                    ~~^~~~~~~~~~~
input/code.cpp:19:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (as.size() > n) return {};
       ~~~~~~~~~~^~~
input/code.cpp:23:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if (as.size() < n) return {};
      ~~~~~~~~~~^~~
input/code.cpp: In function 'void solve()':
input/code.cpp:65:4: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
    for (auto v : res) cout << v + minv << ' '; cout << '\n';
    ^~~
input/code.cpp:65:48: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
    for (auto v : res) cout << v + minv << ' '; cout << '\n';...

Code

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll MOD = (ll)1e9 + 7;
vector<ll> test(ll n, vector<ll> bs) {
vector<ll> as = {0};
multiset<ll> expected;
for (ll v : bs) {
auto it = expected.find(v);
if (it == expected.end()) {
for (int i = 1; i < as.size(); ++i) {
expected.insert(as[i] + v);
}
as.push_back(v);
} else {
expected.erase(it);
}
if (as.size() > n) return {};
}
// Check validity
if (as.size() < n) return {};
for (int i = 0; i+1 < n; ++i) {
if (as[i] > as[i+1]) return {};
}
vector<ll> sums;
for (int i = 0; i < n; ++i) {
for (int j = i+1; j < n; ++j) {
sums.push_back(as[i] + as[j]);
}
}
sort(sums.begin(), sums.end());
if (sums != bs) return {};
return as;
}
void solve() {
int n;
cin >> n;
int m = n*(n-1) / 2;
vector<ll> bs(m);
for (ll& v : bs) cin >> v;
sort(bs.begin(), bs.end());
// If we were guaranteed that the minimum would be zero, the problem would be easy to solve
// Can we find the minimum value in some n^2 attempts? YES:
// Smallest value must equal bs[0] = as[0] + as[1]
// Second smallest must equal bs[1] = as[0] + as[2]
// Loop which value equals bs[2] = as[1] + as[2].
// -> At worst, the nth pair!
// Minimum is 2*bs[0] - bs[1] - bs[2]
// Subtract twice that from all values
for (int i = 2; i < n; ++i) {
ll minv = (bs[0] + bs[1] - bs[i]) / 2;
vector<ll> tmp = bs;
for (ll& v : tmp) v -= 2*minv;
auto res = test(n, tmp);
if (! res.empty()) {
for (auto v : res) cout << v + minv << ' '; cout << '\n';
return;
}
}
cout << "-1\n";
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
solve();
}

Test details

Test 1

Group: 1, 2, 3

Verdict:

input
10
1
2
3
4
...

correct output
2
8
34
148
650
...

user output
-1

Test 2

Group: 2, 3

Verdict:

input
100
1
2
3
4
...

correct output
2
8
34
148
650
...

user output
-1

Test 3

Group: 3

Verdict:

input
100
996306
650655
896240
821967
...

correct output
87350005
606189151
122595036
193572715
227926807
...

user output
-1