//Pantyhose(black) + glasses = infinity
#include <bits/stdc++.h>
using namespace std;
#define debug(x) cerr << #x << " = " << x << '\n';
#define BP() cerr << "OK!\n";
#define PR(A, n) {cerr << #A << " = "; for (int _=1; _<=n; ++_) cerr << A[_] << ' '; cerr << '\n';}
#define PR0(A, n) {cerr << #A << " = "; for (int _=0; _<n; ++_) cerr << A[_] << ' '; cerr << '\n';}
#define FILE_NAME "data"
const int64_t INF = 1e18;
int n;
int64_t c;
vector<int64_t> d, v, q;
map<int64_t, int> idx;
struct fenwick_tree {
int n;
vector<int64_t> bit;
fenwick_tree(int n): n(n) {
bit.resize(n+1, -INF);
}
void upd(int idx, int64_t val) {
for (; idx<=n; idx += idx & -idx)
bit[idx] = max(bit[idx], val);
}
int64_t get(int idx) {
int64_t res = -INF;
for (; idx>0; idx -= idx & -idx)
res = max(res, bit[idx]);
return res;
}
};
void init(int64_t x) {
for (int i=0; i<n; ++i)
q.push_back(d[i]);
sort(q.begin(), q.end());
vector<int64_t> b;
for (int i=0; i<n; ++i) {
b.push_back(-d[i]-v[i]);
b.push_back(v[i]-d[i]-x-1);
}
sort(b.begin(), b.end());
b.resize(unique(b.begin(), b.end()) - b.begin());
idx.clear();
for (int i=0; i<b.size(); ++i)
idx[b[i]] = i + 1;
}
bool check(int64_t x) {
int64_t l1, r1, l2, r2;
l1 = l2 = -INF;
r1 = r2 = INF;
fenwick_tree bit1(2*n), bit2(2*n);
init(x);
for (int i=n-1; i>=0; --i) {
int tmp2 = idx[v[i]-d[i]-x-1];
l1 = max(l1, bit1.get(tmp2)+d[i]-x+c+v[i]);
r1 = min(r1, -bit2.get(tmp2)+d[i]+x-c-v[i]);
l2 = max(l2, bit2.get(tmp2)+d[i]-x+c+v[i]);
r2 = min(r2, -bit1.get(tmp2)+d[i]+x-c-v[i]);
// if (i==0)
// debug(bit1.get(tmp2));
int tmp1 = idx[-d[i]-v[i]];
bit1.upd(tmp1, d[i]+v[i]);
bit2.upd(tmp1, -d[i]+v[i]);
// debug(-d[i]+v[i]);
}
// debug(v[3]);
// cerr << l1 << ' ' << r1 << ' ' << l2 << ' ' << r2 << '\n';
for (int i=0; i<n; ++i) {
int64_t L = max(l1-d[i], d[i]-r2);
int64_t R = min(r1-d[i], d[i]-l2);
auto it = lower_bound(q.begin(), q.end(), L);
if (it!=q.end() && *it<=R)
return true;
}
return false;
}
int64_t find_shortcut(int _n, vector<int> _l, vector<int> _d, int _c) {
c = _c;
n = _n;
for (auto x : _d)
v.push_back(x);
for (auto x : _l)
d.push_back(x);
d.insert(d.begin(), 0);
for (int i=1; i<d.size(); ++i)
d[i] += d[i-1];
// PR0(v, n);
// debug(check(1862645150));
int64_t l = 1, r = INF;
for (int64_t mid=(l+r)/2; mid!=l && r!=mid; mid=(l+r)/2) {
if (check(mid))
r = mid;
else
l = mid;
}
for (int64_t i=l; i<=r; ++i) {
if (check(i))
return i;
}
return 0;
}
int main() {
#ifdef GLASSES_GIRL
freopen(FILE_NAME".in", "r", stdin);
freopen(FILE_NAME".out", "w", stdout);
#endif
ios::sync_with_stdio(0); cin.tie(0);
int n, c;
cin >> n >> c;
vector<int> l(n-1), d(n);
for (int i=0; i+1<n; ++i)
cin >> l[i];
for (int i=0; i<n; ++i)
cin >> d[i];
cout << find_shortcut(n, l, d, c);
}
Compilation message
shortcut.cpp: In function 'void init(int64_t)':
shortcut.cpp:60:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for (int i=0; i<b.size(); ++i)
~^~~~~~~~~
shortcut.cpp: In function 'int64_t find_shortcut(int, std::vector<int>, std::vector<int>, int)':
shortcut.cpp:117:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for (int i=1; i<d.size(); ++i)
~^~~~~~~~~
/tmp/ccWn6ptP.o: In function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'
/tmp/ccheBJ7n.o:shortcut.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status
