#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define X first
#define Y second
#define y0 y12
#define y1 y22
#define INF 987654321987654321
#define PI 3.141592653589793238462643383279502884
#define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
#define fdn(i,a,b,c) for(int (i)=(a);(i)>=(b);(i)-=(c))
#define MEM0(a) memset((a),0,sizeof(a));
#define MEM_1(a) memset((a),-1,sizeof(a));
#define ALL(a) a.begin(),a.end()
#define SYNC ios_base::sync_with_stdio(false);cin.tie(0)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> Pi;
typedef pair<ll, ll> Pll;
typedef pair<ld, ld> Pd;
typedef vector<int> Vi;
typedef vector<ll> Vll;
typedef vector<double> Vd;
typedef vector<Pi> VPi;
typedef vector<Pll> VPll;
typedef vector<Pd> VPd;
typedef tuple<int, int, int> iii;
typedef tuple<int, int, int, int> iiii;
typedef tuple<ll, ll, ll> LLL;
typedef vector<iii> Viii;
typedef vector<LLL> VLLL;
typedef complex<double> base;
const int MOD = 998244353;
ll POW(ll a, ll b, ll MMM = MOD) { ll ret = 1; for (; b; b >>= 1, a = (a*a) % MMM)if (b & 1)ret = (ret*a) % MMM; return ret; }
ll gcd(ll a, ll b) { return b ? gcd(b, a%b) : a; }
ll lcm(ll a, ll b) { if (a == 0 || b == 0)return a + b; return a*(b / gcd(a, b)); }
int dx[] = { 0,1,0,-1,1,1,-1,-1 }, dy[] = { 1,0,-1,0,1,-1,1,-1 };
int n,k;
ll t,a[1000];
Pll d[1000][1000];
bool ok(ll m)
{
fup(i,0,n-1,1)fup(j,0,n-1,1)d[i][j]=mp(INF,-INF);
d[k][k]=mp(a[k],a[k]);
fup(kk,1,n-1,1)
{
fup(i,0,n-1-kk,1)
{
int j=i+kk;
if(d[i+1][j].X<=d[i+1][j].Y && d[i+1][j].X-t*m<=a[i]+t*m*kk)
{
d[i][j].X=min(d[i][j].X,max(d[i+1][j].X-t*m,a[i]-t*m*kk));
d[i][j].Y=max(d[i][j].Y,min(d[i+1][j].Y+t*m,a[i]+t*m*kk));
}
if(d[i][j-1].X<=d[i][j-1].Y && d[i][j-1].X+t*m>=a[j]-t*m*kk)
{
d[i][j].X=min(d[i][j].X,max(d[i][j-1].X-t*m,a[j]-t*m*kk));
d[i][j].Y=max(d[i][j].Y,min(d[i][j-1].Y+t*m,a[j]+t*m*kk));
}
}
}
return d[0][n-1].X<=d[0][n-1].Y;
}
int main() {
scanf("%d%d%lld",&n,&k,&t);k--;
fup(i,0,n-1,1)scanf("%lld",a+i);
ll l=1,r=1000000000;
while(l<=r)
{
ll m=l+r>>1;
if(ok(m))r=m-1;
else l=m+1;
}
printf("%lld",l);
}
Compilation message
sparklers.cpp: In function 'int main()':
sparklers.cpp:75:9: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
ll m=l+r>>1;
~^~
sparklers.cpp:70:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d%lld",&n,&k,&t);k--;
~~~~~^~~~~~~~~~~~~~~~~~~~~
sparklers.cpp:71:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
fup(i,0,n-1,1)scanf("%lld",a+i);
~~~~~^~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
376 KB |
Output is correct |
| 2 |
Incorrect |
4 ms |
376 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
376 KB |
Output is correct |
| 2 |
Incorrect |
4 ms |
376 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
376 KB |
Output is correct |
| 2 |
Incorrect |
4 ms |
376 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
