#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
const int inf = 1e9;
const int maxn = 100010;
int n;
int a[maxn];
struct segtree {
struct node {
int minval, maxval;
node() {}
node(int x, int y) : minval(x), maxval(y) {}
};
node tree[4*maxn];
inline node merge(node a, node b) {
return node(min(a.minval, b.minval), max(a.maxval, b.maxval));
}
segtree() {}
void build(int v, int tl, int tr) {
if (tl == tr) {
tree[v].minval = tree[v].maxval = a[tl];
} else {
int tm = (tl + tr) / 2;
build(2*v, tl, tm);
build(2*v+1, tm+1, tr);
tree[v] = merge(tree[2*v], tree[2*v+1]);
}
}
node query(int v, int tl, int tr, int l, int r) {
if (l > r) return node(inf, -inf);
if (l <= tl && tr <= r) return tree[v];
int tm = (tl + tr) / 2;
return merge(query(2*v, tl, tm, l, min(r, tm)),
query(2*v+1, tm+1, tr, max(l, tm+1), r));
}
} tree;
int main() {
ios::sync_with_stdio(false); cin.tie(0);
cin >> n;
for (int i = 0; i < n; ++i) {
cin >> a[i];
}
tree.build(1, 0, n-1);
int ans = 2*inf;
for (int i = 0; i < n; ++i) {
// assume a[i] is min value
// find min l <= i so that min(a[l], a[l+1], ..., a[i]) is a[i]
// find max r >= i so that min(a[i], a[i+1], ..., a[r]) is a[i]
// ans: max(a[l], a[l+1], ..., a[r-1], a[r]) - a[i]
int lo, mid, hi, l, r;
lo = 0, hi = i-1, l = i;
while (lo <= hi) {
mid = (lo + hi) / 2;
auto res = tree.query(1, 0, n-1, mid, i);
if (res.minval == a[i]) {
l = mid;
hi = mid-1;
} else {
lo = mid+1;
}
}
lo = i+1, hi = n-1, r = i;
while (lo <= hi) {
mid = (lo + hi) / 2;
auto res = tree.query(1, 0, n-1, i, mid);
if (res.minval == a[i]) {
r = mid;
lo = mid+1;
} else {
hi = mid-1;
}
}
if (l < r) {
ans = min(ans, tree.query(1, 0, n-1, l, r).maxval - a[i]);
}
}
cout << ans << endl;
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
| 2 |
Correct |
2 ms |
376 KB |
Output is correct |
| 3 |
Correct |
10 ms |
376 KB |
Output is correct |
| 4 |
Correct |
10 ms |
376 KB |
Output is correct |
| 5 |
Incorrect |
713 ms |
3704 KB |
Output isn't correct |
| 6 |
Incorrect |
711 ms |
3832 KB |
Output isn't correct |
| 7 |
Incorrect |
711 ms |
3576 KB |
Output isn't correct |
