CSES - Datatähti 2025 alku - Results
Submission details
Task:Robotti
Sender:TNT
Submission time:2024-10-31 20:34:58 +0200
Language:C++ (C++20)
Status:READY
Result:100
Feedback
groupverdictscore
#1ACCEPTED30
#2ACCEPTED70
Test results
testverdicttimegroup
#1ACCEPTED0.00 s1, 2details
#2ACCEPTED0.00 s1, 2details
#3ACCEPTED0.00 s1, 2details
#4ACCEPTED0.00 s1, 2details
#5ACCEPTED0.00 s1, 2details
#6ACCEPTED0.00 s1, 2details
#7ACCEPTED0.00 s1, 2details
#8ACCEPTED0.00 s1, 2details
#9ACCEPTED0.00 s1, 2details
#10ACCEPTED0.00 s1, 2details
#11ACCEPTED0.00 s1, 2details
#12ACCEPTED0.00 s2details
#13ACCEPTED0.00 s2details
#14ACCEPTED0.00 s2details
#15ACCEPTED0.00 s2details
#16ACCEPTED0.00 s2details
#17ACCEPTED0.01 s2details
#18ACCEPTED0.01 s2details
#19ACCEPTED0.01 s2details
#20ACCEPTED0.01 s2details
#21ACCEPTED0.01 s2details
#22ACCEPTED0.01 s2details
#23ACCEPTED0.01 s2details
#24ACCEPTED0.01 s2details

Compiler report

input/code.cpp: In function 'std::vector<int> CollectCoins(int, std::string, std::vector<int>, std::size_t)':
input/code.cpp:20:83: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |                 while ((((int)RobotPos-PrevSearch>=0) || ((int)RobotPos+PrevSearch<Layout.length())) && (DistanceLeft == -1 && DistanceRight == -1)) {
      |                                                           ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~
input/code.cpp:20:119: warning: comparison of integer expressions of different signedness: 'std::size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   20 |                 while ((((int)RobotPos-PrevSearch>=0) || ((int)RobotPos+PrevSearch<Layout.length())) && (DistanceLeft == -1 && DistanceRight == -1)) {
      |                                                                                                          ~~~~~...

Code

#include <iostream>
#include <ostream>
#include <string>
#include <vector>
std::vector<int> CollectCoins(int Rooms, std::string Layout, std::vector<int> Output, std::size_t RobotPos = 0) {
while (true) {
if (RobotPos == 0) RobotPos = Layout.find('R');
//std::cout << RobotPos << "\n";
// Failsafe initializations
std::size_t CoinLeft = -1;
std::size_t DistanceLeft = -1;
std::size_t CoinRight = -1;
std::size_t DistanceRight = -1;
// Iteratively search for coins
int SearchDepth = 5;
int PrevSearch = 0;
while ((((int)RobotPos-PrevSearch>=0) || ((int)RobotPos+PrevSearch<Layout.length())) && (DistanceLeft == -1 && DistanceRight == -1)) {
if (RobotPos != (size_t)0) {
int SearchStart = (int)RobotPos-PrevSearch;
if (SearchStart <= 0) SearchStart = 0;
for (int i = SearchStart; (i>=SearchStart-SearchDepth) && (i>=0); i--) {
//std::cout << "left: " << i << "\n";
if (Layout[i]=='*') {
CoinLeft = i;
break;
}
}
//std::cout << CoinLeft << "\n";
if (CoinLeft!=-1) DistanceLeft = RobotPos - CoinLeft;
}
if (RobotPos != (size_t)(Rooms-1)) {
int SearchStart = (int)RobotPos+PrevSearch;
if (SearchStart >= Layout.length()) SearchStart = Layout.length()-1;
for (int i = SearchStart; (i<=SearchStart+SearchDepth) && (i<Layout.length()); i++) {
//std::cout << "right: "<< i << "\n";
if (Layout[i]=='*') {
CoinRight = i;
break;
}
}
//std::cout << CoinRight << "\n";
if (CoinRight!=-1) DistanceRight = CoinRight - RobotPos;
}
PrevSearch += SearchDepth;
//SearchDepth *= 2;
}
/*if (DistanceLeft < DistanceRight) {
std::cout << "robot: "<< (int)RobotPos-PrevSearch << " " << RobotPos << " " << (int)RobotPos+PrevSearch << "\n";;
std::cout << "left: "<< DistanceLeft << " " << CoinLeft << "\n"
<< "right: "<< DistanceRight << " " << CoinRight << "\n" << std::endl;
throw;
}*/
if (DistanceLeft==DistanceRight || ((CoinLeft == (size_t)-1) && (CoinRight == (size_t)-1))) {
/*std::cout << "Returning with: " << "\n"
<< "layout:\n" << Layout << "\n"
<< "left: "<< DistanceLeft << " " << CoinLeft << "\n"
<< "right: "<< DistanceRight << " " << CoinRight << "\n" << std::endl;
*/
return Output;
}
Layout[RobotPos] = '.';
Output[1]++;
//std::cout << "Robot at: " << RobotPos << "\n";
if (DistanceLeft<DistanceRight) {
RobotPos = CoinLeft;
Output[0] += DistanceLeft;
Layout[CoinLeft] = 'R';
} else {
RobotPos = CoinRight;
Output[0] += DistanceRight;
Layout[CoinRight] = 'R';
}
//std::cout << Layout << "\n";
//std::cout << "Robot at: " << RobotPos << "\n";
/*
std::cout << "SearchDepth: " << SearchDepth/2 << "\n";
std::cout << "CoinLeft: " << CoinLeft << "\n";
std::cout << "CoinRight: " << CoinRight << "\n";
std::cout << "Distances: " << DistanceLeft << " " << DistanceRight << "\n\n";
*/
}
}
int main () {
// Input:
// n rooms
// Building layout
// e.g.
// 20
// **.*......*.R*...*..
// * = coin; . = empty; R = robot
int Rooms;
std::string Layout;
std::cin >> Rooms;
std::cin >> Layout;
// GOAL: Find the max number of coins the robot can collect by always going to
// the closest coin
std::vector<int> Output = {0,0};
Output = CollectCoins(Rooms, Layout, Output);
int Steps = Output[0];
int Coins = Output[1];
std::cout << Steps << " " << Coins << "\n";
}

Test details

Test 1

Group: 1, 2

Verdict: ACCEPTED

input
1
R

correct output
0 0

user output
0 0

Test 2

Group: 1, 2

Verdict: ACCEPTED

input
10
...R......

correct output
0 0

user output
0 0

Test 3

Group: 1, 2

Verdict: ACCEPTED

input
10
**.R...***

correct output
12 5

user output
12 5

Test 4

Group: 1, 2

Verdict: ACCEPTED

input
10
***R******

correct output
0 0

user output
0 0

Test 5

Group: 1, 2

Verdict: ACCEPTED

input
1000
R................................

correct output
947 9

user output
947 9

Test 6

Group: 1, 2

Verdict: ACCEPTED

input
1000
.................................

correct output
886 9

user output
886 9

Test 7

Group: 1, 2

Verdict: ACCEPTED

input
1000
.....*..*....**..**..*......*....

correct output
1287 400

user output
1287 400

Test 8

Group: 1, 2

Verdict: ACCEPTED

input
1000
************.*****************...

correct output
0 0

user output
0 0

Test 9

Group: 1, 2

Verdict: ACCEPTED

input
1000
******************************...

correct output
0 0

user output
0 0

Test 10

Group: 1, 2

Verdict: ACCEPTED

input
1000
R*****************************...

correct output
999 999

user output
999 999

Test 11

Group: 1, 2

Verdict: ACCEPTED

input
1000
******************************...

correct output
999 999

user output
999 999

Test 12

Group: 2

Verdict: ACCEPTED

input
10000
.......**........*...........*...

correct output
10971 999

user output
10971 999

Test 13

Group: 2

Verdict: ACCEPTED

input
10000
*..*....*......*.....*..*........

correct output
9999 999

user output
9999 999

Test 14

Group: 2

Verdict: ACCEPTED

input
10000
*.*.*...**.*...*....**.**.**.....

correct output
18766 5000

user output
18766 5000

Test 15

Group: 2

Verdict: ACCEPTED

input
10000
R*****************************...

correct output
9999 9999

user output
9999 9999

Test 16

Group: 2

Verdict: ACCEPTED

input
10000
******************************...

correct output
9999 9999

user output
9999 9999

Test 17

Group: 2

Verdict: ACCEPTED

input
200000
.................................

correct output
0 0

user output
0 0

Test 18

Group: 2

Verdict: ACCEPTED

input
200000
.................................

correct output
299934 10000

user output
299934 10000

Test 19

Group: 2

Verdict: ACCEPTED

input
200000
**.***....**..**.....***.*..*....

correct output
299998 100000

user output
299998 100000

Test 20

Group: 2

Verdict: ACCEPTED

input
200000
******************************...

correct output
0 0

user output
0 0

Test 21

Group: 2

Verdict: ACCEPTED

input
200000
R................................

correct output
133765 3

user output
133765 3

Test 22

Group: 2

Verdict: ACCEPTED

input
200000
R................................

correct output
199982 5000

user output
199982 5000

Test 23

Group: 2

Verdict: ACCEPTED

input
200000
R*****************************...

correct output
199999 199999

user output
199999 199999

Test 24

Group: 2

Verdict: ACCEPTED

input
200000
******************************...

correct output
199999 199999

user output
199999 199999