
Part of series: PS
14438 BOJ
문제
접근
세그먼트 트리를 이용해 해결하였다.
최솟값을 찾는 세그먼트 트리를 활용해 해결하였다.
코드
#include <bits/stdc++.h>
#include <climits>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef const ll cll;
typedef queue<ll> qll;
typedef queue<pll> qpll;
typedef priority_queue<ll> pqll;
typedef priority_queue<pll> pqpll;
typedef vector<ll> vll;
typedef vector<pll> vpll;
typedef vector<vll> vvll;
typedef vector<vpll> vvpll;
#define FOR1(a, A) for (ll a = 0; a < A; ++a)
#define FOR2(a, b, A, B) \
for (ll a = 0; a < A; ++a) \
for (ll b = 0; b < B; ++b)
cll N = 1e5, INF = 1e9 + 1;
ll n, A[N] = {}, m, seg[10 * N] = {};
ll fill(ll s, ll e, ll node) {
if (s == e) {
return seg[node] = A[s];
}
ll mid = (s + e) / 2;
return seg[node] =
min(fill(s, mid, node * 2), fill(mid + 1, e, node * 2 + 1));
}
ll update(const ll i, ll s, ll e, ll node) {
if (s == e) {
return seg[node] = A[i];
}
ll mid = (s + e) / 2;
if (i <= mid) {
return seg[node] = min(seg[node * 2 + 1], update(i, s, mid, node * 2));
} else {
return seg[node] = min(seg[node * 2], update(i, mid + 1, e, node * 2 + 1));
}
}
ll find(const ll i, const ll j, ll s, ll e, ll node) {
if (i <= s && e <= j) {
return seg[node];
} else if (j < s || e < i) {
return INF;
}
ll mid = (s + e) / 2;
return min(find(i, j, s, mid, node * 2),
find(i, j, mid + 1, e, node * 2 + 1));
}
int main(void) {
ios::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
cin >> n;
for (ll i = 0; i < n; ++i) {
cin >> A[i];
}
fill(0, n - 1, 1);
cin >> m;
for (ll q, i, j, l = 0; l < m; ++l) {
cin >> q >> i >> j;
--i;
if (q == 1) {
A[i] = j;
update(i, 0, n - 1, 1);
} else {
--j;
cout << find(i, j, 0, n - 1, 1) << "\n";
}
}
return 0;
}