#include <bits/stdc++.h>
using namespace std;
int n;
long long vinit[5010];
long long dp[25000000];
priority_queue <pair <long long , int> > h;
int encode (int x , int y){
x--;
y--;
return x * n + y;
}
pair <int , int> decode (int cod){
return make_pair(cod / n + 1 , cod % n + 1);
}
void muchie (int x1 , int y1 , int x2 , int y2 , long long cost){
int nod , vecin;
nod = encode(x1 , y1);
vecin = encode(x2 , y2);
if (dp[vecin] > dp[nod] + cost){
dp[vecin] = dp[nod] + cost;
h.push(make_pair(-dp[vecin] , vecin));
}
}
int main()
{
FILE *fin = stdin;
FILE *fout = stdout;
int i , ers , nod , j;
long long cost;
pair <int , int> actual;
fscanf (fin,"%d",&n);
for (i = 1 ; i <= n ; i++)
fscanf (fin,"%lld",&vinit[i]);
ers = 0;
for (i = 2 ; i < n ; i++){
if ((vinit[i - 1] <= vinit[i] && vinit[i] <= vinit[i + 1]) || (vinit[i - 1] >= vinit[i] && vinit[i] >= vinit[i + 1]))
ers++; /// il stergi pe vinit[i]
else vinit[i - ers] = vinit[i];
}
vinit[n - ers] = vinit[n];
n -= ers;
/// acum vinit ul e "condensat"
for (i = 0 ; i < n * n ; i++)
dp[i] = 2000000000000000000;
dp[encode(1 , n - 1)] = 0;
h.push(make_pair(0 , encode(1 , n - 1)));
while (!h.empty()){
cost = -h.top().first;
nod = h.top().second;
h.pop();
actual = decode(nod);
if (dp[nod] != cost)
continue;
i = actual.first;
j = actual.second;
if (i == j || i == j + 1){
fprintf (fout,"%lld",cost);
return 0;
}
/// ------------------------------------------------------------------------
if (j != 1 && vinit[i] == vinit[j])
muchie (i , j , i , j - 1 , 0);
if (j != n && vinit[i] == vinit[j + 1])
muchie (i , j , i , j + 1 , 0);
if (vinit[j] < vinit[j + 1]){ /// segm e crescator
if (i != n){ /// ma duc in nodul i + 1, deci nu parasesc segm
if (vinit[i + 1] > vinit[i] && vinit[i + 1] <= vinit[j + 1]){
muchie (i , j , i + 1 , j , vinit[i + 1] - vinit[i]); /// se pastreaza segmentul
}
else if (vinit[i + 1] < vinit[i] && vinit[i + 1] >= vinit[j]){
muchie (i , j , i + 1 , j , vinit[i] - vinit[i + 1]);
}
}
if (i != 1){ /// ma duc in nodul i - 1, raman pe acelasi segm
if (vinit[i - 1] > vinit[i] && vinit[i - 1] <= vinit[j + 1]){
muchie (i , j , i - 1 , j , vinit[i - 1] - vinit[i]); /// se pastreaza segmentul
}
else if (vinit[i - 1] < vinit[i] && vinit[i - 1] >= vinit[j]){
muchie (i , j , i - 1 , j , vinit[i] - vinit[i - 1]);
}
}
/// --------------------------------------------------
/// sunt intre j si j + 1
/// vreau sa ma mut in j, adc cobor
if (i != n && vinit[i] > vinit[i + 1] && vinit[i] - vinit[i + 1] >= vinit[i] - vinit[j]){
muchie (i , j , j , i , vinit[i] - vinit[j]);
}
if (i != 1 && vinit[i] > vinit[i - 1] && vinit[i] - vinit[i - 1] >= vinit[i] - vinit[j]){
muchie (i , j , j , i - 1 , vinit[i] - vinit[j]);
}
/// in j + 1 , adc urc
if (i != n && vinit[i] < vinit[i + 1] && vinit[i + 1] - vinit[i] >= vinit[j + 1] - vinit[i]){
muchie (i , j , j + 1 , i , vinit[j + 1] - vinit[i]);
}
if (i != 1 && vinit[i] < vinit[i - 1] && vinit[i - 1] - vinit[i] >= vinit[j + 1] - vinit[i]){
muchie (i , j , j + 1 , i - 1 , vinit[j + 1] - vinit[i]);
}
}
else { /// segm e descrescator
if (i != n){ /// ma duc in nodul i + 1, deci nu parasesc segm
if (vinit[i + 1] > vinit[i] && vinit[i + 1] <= vinit[j]){
muchie (i , j , i + 1 , j , vinit[i + 1] - vinit[i]); /// se pastreaza segmentul
}
else if (vinit[i + 1] < vinit[i] && vinit[i + 1] >= vinit[j + 1]){
muchie (i , j , i + 1 , j , vinit[i] - vinit[i + 1]);
}
}
if (i != 1){ /// ma duc in nodul i - 1, raman pe acelasi segm
if (vinit[i - 1] > vinit[i] && vinit[i - 1] <= vinit[j]){
muchie (i , j , i - 1 , j , vinit[i - 1] - vinit[i]); /// se pastreaza segmentul
}
else if (vinit[i - 1] < vinit[i] && vinit[i - 1] >= vinit[j + 1]){
muchie (i , j , i - 1 , j , vinit[i] - vinit[i - 1]);
}
}
/// --------------------------------------------------
/// sunt intre j si j + 1
/// vinitreau sa ma mut in j, adc URC
if (i != n && vinit[i] < vinit[i + 1] && vinit[i + 1] - vinit[i] >= vinit[j] - vinit[i]){
muchie (i , j , j , i , vinit[j] - vinit[i]);
}
if (i != 1 && vinit[i] < vinit[i - 1] && vinit[i - 1] - vinit[i] >= vinit[j] - vinit[i]){
muchie (i , j , j , i - 1 , vinit[j] - vinit[i]);
}
/// vinitreau sa ma duc in j + 1 adica cobor
if (i != n && vinit[i] > vinit[i + 1] && vinit[i] - vinit[i + 1] >= vinit[i] - vinit[j + 1]){
muchie (i , j , j + 1 , i , vinit[i] - vinit[j + 1]);
}
if (i != 1 && vinit[i] > vinit[i - 1] && vinit[i] - vinit[i - 1] >= vinit[i] - vinit[j + 1]){
muchie (i , j , j + 1 , i - 1 ,vinit[i] - vinit[j + 1]);
}
}
}
fprintf (fout,"NO");
return 0;
}
Compilation message
climbers.cpp: In function 'int main()':
climbers.cpp:42:12: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
42 | fscanf (fin,"%d",&n);
| ~~~~~~~^~~~~~~~~~~~~
climbers.cpp:44:16: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
44 | fscanf (fin,"%lld",&vinit[i]);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
364 KB |
Output is correct |
| 2 |
Correct |
1 ms |
1004 KB |
Output is correct |
| 3 |
Correct |
6 ms |
8172 KB |
Output is correct |
| 4 |
Correct |
45 ms |
70636 KB |
Output is correct |
| 5 |
Correct |
132 ms |
195948 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
364 KB |
Output is correct |
| 2 |
Correct |
1 ms |
384 KB |
Output is correct |
| 3 |
Correct |
1 ms |
492 KB |
Output is correct |
| 4 |
Correct |
1 ms |
364 KB |
Output is correct |
| 5 |
Correct |
1 ms |
1516 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
384 KB |
Output is correct |
| 2 |
Correct |
1 ms |
1004 KB |
Output is correct |
| 3 |
Correct |
75 ms |
7532 KB |
Output is correct |
| 4 |
Correct |
153 ms |
64492 KB |
Output is correct |
| 5 |
Correct |
191 ms |
64108 KB |
Output is correct |
| 6 |
Correct |
219 ms |
121964 KB |
Output is correct |
| 7 |
Correct |
222 ms |
115052 KB |
Output is correct |
| 8 |
Correct |
217 ms |
176108 KB |
Output is correct |
| 9 |
Correct |
295 ms |
179692 KB |
Output is correct |
| 10 |
Correct |
263 ms |
175468 KB |
Output is correct |
