#pragma GCC optimize("Ofast,O3,unroll-loops")
#pragma GCC target("avx,avx2")
#include <bits/stdc++.h>
using namespace std;
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define bpc(x) __builtin_popcount(x)
#define bpcll(x) __builtin_popcountll(x)
#define MP make_pair
//#define endl '\n'
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
typedef long long ll;
const int MOD = 1e9 + 7;
const int N = 5e5 + 30;
int a[N], b[N];
void solve(){
int n;
cin >> n;
for (int i = 1; i <= n; i++) cin >> a[i] >> b[i];
deque<int> before, after;
ll sum = 0;
for (int i = 2; i <= n; i++){
if (a[i] > b[i]) after.push_back(i);
sum += a[i] - b[i];
}
ll ans = 0;
auto transfer = [&](int to, int from) -> void{
int mn = min(a[from] - b[from], b[to] - a[to]);
// cout << from << " -> " << to << ": " << mn << " units\n";
ans += (ll) mn * abs(from - to);
a[from] -= mn;
a[to] += mn;
if (from > to) sum -= mn;
};
for (int i = 1; i <= n; i++){
if (!after.empty() && after.front() == i) after.pop_front();
if (a[i] >= b[i]){
if (a[i] > b[i]) before.push_back(i);
continue;
}
while (a[i] < b[i]){
int x = -1, y = -1;
if (!before.empty()) x = before.back();
if (sum > 0) y = after.front();
if (y != -1 && (x == -1 || y - i < i - x)){
transfer(i, y);
if (a[y] == b[y]) after.pop_front();
} else if (x != -1){
transfer(i, x);
if (a[x] == b[x]) before.pop_back();
} else {
break;
}
}
assert(a[i] == b[i]);
}
cout << ans << endl;
}
int main(){
clock_t startTime = clock();
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
int test_cases = 1;
// cin >> test_cases;
for (int test = 1; test <= test_cases; test++){
//cout << (solve() ? "YES" : "NO") << endl;
solve();
}
#ifdef LOCAL
cerr << "Time: " << int((double) (clock() - startTime) / CLOCKS_PER_SEC * 1000) << " ms" << endl;
#endif
return 0;
}
Compilation message
bulves.cpp: In function 'int main()':
bulves.cpp:81:13: warning: unused variable 'startTime' [-Wunused-variable]
81 | clock_t startTime = clock();
| ^~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Runtime error |
1 ms |
596 KB |
Execution killed with signal 6 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Runtime error |
1 ms |
596 KB |
Execution killed with signal 6 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Runtime error |
1 ms |
596 KB |
Execution killed with signal 6 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Runtime error |
1 ms |
596 KB |
Execution killed with signal 6 |
4 |
Halted |
0 ms |
0 KB |
- |