oj.uz

Submission #384886

# Submission time Handle Problem Language Result Execution time Memory
384886 2021-04-02T14:45:54 Z cpp219 Watching (JOI13_watching) C++14
50 / 100
 840 ms 262148 KB 
#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define fs first
#define sc second
using namespace std;
const ll N = 2e3 + 6;
const ll Log2 = 19;
const ll inf = 1e9 + 7;
typedef pair<ll,ll> LL;
vector<ll> v;
ll n,P,Q,a[N],dp[N][2*N],val,jump[N][2]; /// 0 if short jump    1 long jump

ll Find(ll x){
	ll p = lower_bound(v.begin(),v.end(),x) - v.begin() + 1;
	return p;
}

ll f(ll pos,ll p){
	if (pos > n) return 0;
	if (dp[pos][p] != -1) return dp[pos][p];
	ll ans = inf;
	if (p) ans = f(jump[pos][0],p - 1);
	ans = min(ans,1 + f(jump[pos][1],p));
	return dp[pos][p] = ans;
}

bool chk(ll m){
	memset(dp,-1,sizeof(dp)); val = m;
	for (ll i = 1;i <= n;i++){
        jump[i][0] = Find(a[i] + m); jump[i][1] = Find(a[i] + 2*m);
    }
	return f(1,P) <= Q;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    #define task "tst"
    if (fopen(task".in", "r")){
        freopen(task".in", "r", stdin);
        //freopen(task".out", "w", stdout);
    }
    cin>>n>>P>>Q;
    for (ll i = 1;i <= n;i++) cin>>a[i]; sort(a + 1,a + n + 1);
    for (ll i = 1;i <= n;i++) v.push_back(a[i]); v.push_back(inf);
    if (P + Q >= n) return cout<<1,0;
    ll l,m,h; l = 0; h = inf;
    while(l <= h){
    	m = (l + h)/2;
    	if (chk(m)) h = m - 1;
    	else l = m + 1;
	}
	cout<<l;
}

Compilation message

watching.cpp: In function 'int main()':
watching.cpp:45:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   45 |     for (ll i = 1;i <= n;i++) cin>>a[i]; sort(a + 1,a + n + 1);
      |     ^~~
watching.cpp:45:42: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   45 |     for (ll i = 1;i <= n;i++) cin>>a[i]; sort(a + 1,a + n + 1);
      |                                          ^~~~
watching.cpp:46:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   46 |     for (ll i = 1;i <= n;i++) v.push_back(a[i]); v.push_back(inf);
      |     ^~~
watching.cpp:46:50: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   46 |     for (ll i = 1;i <= n;i++) v.push_back(a[i]); v.push_back(inf);
      |                                                  ^
watching.cpp:41:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   41 |         freopen(task".in", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 270 ms 63340 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Correct 269 ms 63340 KB Output is correct
4 Correct 1 ms 364 KB Output is correct
5 Correct 1 ms 364 KB Output is correct
6 Correct 1 ms 364 KB Output is correct
7 Correct 271 ms 63340 KB Output is correct
8 Correct 273 ms 63468 KB Output is correct
9 Correct 272 ms 63340 KB Output is correct
10 Correct 273 ms 63340 KB Output is correct
11 Correct 264 ms 63468 KB Output is correct
12 Correct 273 ms 63400 KB Output is correct
13 Correct 277 ms 63468 KB Output is correct
14 Correct 273 ms 63340 KB Output is correct
15 Correct 270 ms 63340 KB Output is correct

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 275 ms 63472 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Correct 1 ms 492 KB Output is correct
4 Correct 2 ms 364 KB Output is correct
5 Correct 1 ms 364 KB Output is correct
6 Correct 1 ms 364 KB Output is correct
7 Correct 280 ms 63468 KB Output is correct
8 Correct 321 ms 63468 KB Output is correct
9 Correct 439 ms 63596 KB Output is correct
10 Runtime error 840 ms 262148 KB Execution killed with signal 9
11 Halted 0 ms 0 KB -