CHARGES - Editorial

editorial
, ,
114

#include <bits/stdc++.h>
using namespace std;

define ll long long

int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
ll int t;
cin>>t;
for(ll int i=0;i<t;i++)
{
ll int n,k;
cin>>n>>k;
string s;
cin>>s;
ll int a[k+1]={};
for(ll int x=1;x<=k;x++)
{
cin>>a[x];
}
ll int len=0;
for(ll int r=0;r<s.size()-1;r++)
{
// cout<<s[r]<<s[r+1]<<endl;
if(s[r]==s[r+1])
len+=2;
else
len+=1;
}
if(n==1)
{
cout<<“0”<<endl;
continue;
}
//cout<<len<<endl;
for(ll int j=1;j<=k;j++)
{
if(s[a[j]-1]==‘0’)
{
s[a[j]-1]=‘1’;
//cout<<“z”<<endl;
}
else
{
s[a[j]-1]=‘0’;
}
if(s[a[j]-1]==s[a[j]] && a[j]>1 && a[j]<k)
{
len++;
}
if(s[a[j]-1]!=s[a[j]] && a[j]>1 && a[j]<k)
{
len–;
}
if(s[a[j]-1]==s[a[j]-2] && a[j]>1 && a[j]<k)
{
len++;
}
if(s[a[j]-1]!=s[a[j]-2] && a[j]>1 && a[j]<k)
{
len–;
}
if(a[j]==1)
{
if(s[a[j]-1]==s[a[j]])
{
len++;
}
else
{
len–;
}
}
if(a[j]==k)
{
if(s[a[j]-2]==s[a[j]-1])
len++;
else
len–;
}
cout<<len<<endl;
}
}

return 0;

}
can someone tell me why my code is showing wrong answer @darshancool25

115

Please either format your code or (better!) link to your submission - the forum software has mangled it and it won’t compile! :slight_smile:

116

https://www.codechef.com/viewsolution/47363078
the link

1 Like
117 
1
6 4
111010
4 5 6 3
118

thnku vry much …!
I was doing such a silly mistake…!

1 Like
119

By sample test case do you mean

1
3 3
010
2 1 3`
cause it is giving right output for me in Sublime text
120

There’s Undefined Behaviour for you :man_shrugging:

121

Can you please tell me why? I really don’t know. I only use CC IDE or Sublime Text and it’s giving correct output for both for sample test case

122

Out-of-Bounds accesses are Undefined Behaviour, meaning anything can happen - you might get the right answer; you might get the wrong answer; it might crash. It’s almost impossible to predict what will happen.

123

This is giving an output of

9
9
8
6
for me
124

I’m so sorry! It gave AC when I did

if (s[1] != s[0] && n > 1)

I wouldn’t have gone down by a division if I corrected this.
It was failing for the simplest TC,

1 
1 1
1
1
1 Like
125

Thank you I’ll look into it :slight_smile:

1 Like
126

Yeah it worked using pass by reference. Thank you!

1 Like
128

Please either format your code or (better!) link to your submission - the forum software has mangled it and it won’t compile! :slight_smile:

129

Code link

Can anyone plzz tell my error…i have used the similar approach…!!

130

Consider the test input:

1
4 8
0110
1 4 2 1 3 2 1 2
131

I think the case where n==1 is a pretty misleading one and should have been clearly mentioned in the question itself. My output was set to print ‘k’ times as it should be but if n==1, print should be ‘0’ once and NOT ‘k’ times. I only understood this after watching the discussions. This was not mentioned in the video editorial even. :cry:

132

All of the Editorialist, Tester and Setter solutions give:

0
0
0
0
0
0
0
0
0

for the test input:

1
1 9
1
1 1 1 1 1 1 1 1 1

If printing out a single 0 gets AC, I guess the testcases must be pretty weak.

1 Like
133

Can someone please explain why this code is giving Runtime Error?It’s working fine for the given TC,but after submitting it’s giving Runtime Error RE (SIGSEGV).
Thank you!

Solution

134 
[simon@simon-laptop][19:08:05]
[~/devel/hackerrank/otherpeoples]>./compile-latest-cpp.sh 
Compiling cookieg13-CHARGES.cpp
+ g++ -std=c++14 cookieg13-CHARGES.cpp -O3 -g3 -Wall -Wextra -Wconversion -DONLINE_JUDGE -D_GLIBCXX_DEBUG -fsanitize=undefined -ftrapv
cookieg13-CHARGES.cpp: In function ‘int main()’:
cookieg13-CHARGES.cpp:25:17: warning: unused variable ‘i’ [-Wunused-variable]
         int N,K,i,TotalDist=0;
                 ^
+ set +x
Successful
[simon@simon-laptop][19:08:14]
[~/devel/hackerrank/otherpeoples]>echo "1
3 3
010
2 1 3" | ./a.out
cookieg13-CHARGES.cpp:38:23: runtime error: index 2 out of bounds for type 'int [*]'
cookieg13-CHARGES.cpp:42:32: runtime error: index 2 out of bounds for type 'int [*]'
4
3
2