| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 146985 | dongwon0427 | Lightning Rod (NOI18_lightningrod) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
int n;
static char buf[1 << 19]; // size : any number geq than 1024
static int idx = 0;
static int bytes = 0;
static inline int _read() {
if (!bytes || idx == bytes) {
bytes = (int)fread(buf, sizeof(buf[0]), sizeof(buf), stdin);
idx = 0;
}
return buf[idx++];
}
static inline int fastscan() {
int x = 0, s = 1;
int c = _read();
while (c <= 32) c = _read();
if (c == '-') s = -1, c = _read();
while (c > 32) x = 10 * x + (c - '0'), c = _read();
if (s < 0) x = -x;
return x;
}
vector<pii> v;
int main() {
fastscan(n);
pii prv = pii(-1,0);
for(int i=0;i<n;i++) {
int t1,t2;
fastscan(t1); fastscan(t2);
if(t1 != prv.first) {
prv = pii(t1,t2);
v.push_back(prv);
} else if(prv.second < t2) {
prv.second = t2;
v.back().second = t2;
}
}
vector<int> s;
s.push_back(0);
int mx = v[0].first + v[0].second;
for(int i=1;i<v.size();i++) {
pii p = v[i];
if(mx >= p.first + p.second) continue;
mx = p.first + p.second;
while(!s.empty()) {
pii t = v[s.back()];
if(t.second - t.first <= p.second - p.first) s.pop_back();
else break;
}
s.push_back(i);
//for(int x : s) cout<<x<<' ';
//cout<<'\n';
}
cout<<s.size();
return 0;
}