#pragma GCC optimize("O2")
#include <bits/stdc++.h>
#ifdef DEBUG
#include "debug.hpp"
#endif
using namespace std;
#define all(c) (c).begin(), (c).end()
#define traverse(c, it) for(auto it = (c).begin(); it != (c).end(); it++)
#define rep(i, N) for(int i = 0; i < (N); i++)
#define rep1(i, N) for(int i = 1; i <= (N); i++)
#define rep2(i, s, e) for(int i = (s); i <= (e); i++)
#define rep3(i, s, e, d) for(int i = (s); (d) >= 0 ? i <= (e) : i >= (e); i += (d))
#define pb push_back
#ifdef DEBUG
#define debug(x...) {dbg::depth++; string dbg_vals = dbg::to_string(x); dbg::depth--; dbg::fprint(__func__, __LINE__, #x, dbg_vals);}
#define light_debug(x) {dbg::light = 1; dbg::dout << __func__ << ":" << __LINE__ << " " << #x << " = " << x << endl; dbg::light = 0;}
#else
#define debug(x...)
#define light_debug(x)
#endif
template<typename T>
T& ckmin(T& a, T b){ return a = a > b ? b : a; }
template<typename T>
T& ckmax(T& a, T b){ return a = a < b ? b : a; }
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
const int TOO_LESS = -1, TOO_MUCH = 1;
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
#ifdef DEBUG
freopen("debug", "w", stderr);
#endif
int n;
cin >> n;
vi A(n), b(n);
rep(i, n) cin >> A[i] >> b[i];
debug(A, b);
auto check = [=](int x, vi a){
debug(a, x);
a[n - 1] -= x << 1;
a[0] += x;
rep(i, n - 1){
debug(a[i], b[i])
if(a[i] < b[i])
return TOO_LESS;
else
a[i + 1] += (a[i] - b[i]) >> 1, a[i] = b[i];
}
debug(a);
if(a[n - 1] < b[n - 1])
return TOO_MUCH;
else if(a[n - 1] > b[n - 1])
return TOO_LESS;
return 0;
};
int s = 0, e = A[n - 1] / 2;
debug(s, e);
while(s <= e){
int m = (s + e) >> 1;
int t = check(m, A);
if(t == TOO_LESS)
s = m + 1;
else if(t == TOO_MUCH)
e = m - 1;
else{
cout << "Yes\n";
return 0;
}
}
cout << "No\n";
#ifdef DEBUG
dbg::dout << "\nExecution time: " << clock() << "ms\n";
#endif
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
0 ms |
384 KB |
Output is correct |
3 |
Correct |
1 ms |
384 KB |
Output is correct |
4 |
Correct |
0 ms |
384 KB |
Output is correct |
5 |
Incorrect |
1 ms |
384 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
0 ms |
384 KB |
Output is correct |
3 |
Correct |
1 ms |
384 KB |
Output is correct |
4 |
Correct |
0 ms |
384 KB |
Output is correct |
5 |
Incorrect |
1 ms |
384 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
0 ms |
384 KB |
Output is correct |
3 |
Correct |
1 ms |
384 KB |
Output is correct |
4 |
Correct |
0 ms |
384 KB |
Output is correct |
5 |
Incorrect |
1 ms |
384 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |