Can anyone tell what’s wrong with this code?
#include <iostream>
#include <vector>
#include <stack>
using namespace std;
#define ull unsigned long long int
int getK(vector<char> s) {
stack<char> st;
int k=0;
for(int i=0; i<s.size(); i++) {
if(s[i]=='<') {
st.push('<');
}
else { // '>'
if(!st.empty()) {
st.pop();
k++;
}
else {
break;
}
}
}
return k;
}
int main() {
int T;
cin >> T;
while(T--) {
string ss;
cin >> ss;
vector<char> s(ss.begin(),ss.end());
int K = getK(s);
if(K==getK(vector<char>(ss.begin()+1,ss.end()))) cout << 0 << endl;
else cout << K*2 << endl;
}
}
can anyone plz say why this is giving WA ?? Any particular case
https://www.codechef.com/viewsolution/30790003
Kindly check why this is giving WA.
My logic : If ‘<’ increase top pointer. If ‘>’ decrease top pointer and increase length by 2 (1 for < and 1 for >)
Initial top pointer value = -1. If ‘>’ and top pointer is -1 it means no matching ‘<’ encountered…so return the current length of valid string till now.
Solution : CodeChef: Practical coding for everyone
ssjgz
April 5, 2020, 4:21pm
67
Your solution fails on the testcase in the post above yours
Yours is the only solution that I understood properly. Thanks for sharing!
I tried solving this problem with implementing concept of stack but it is giving WA. Although in my PC’s IDE it worked well.
Please once check my solution(CodeChef: Practical coding for everyone ) it’s small.
ssjgz
April 16, 2020, 3:36pm
70
Your solution fails on this testcase (the same as the last few posters in this thread ;))
1 Like
Thanks. I saw your post but forgot to reply. today i just happened to pass by and noticed it
1 Like
I think <<> should give 0 ?
Solution adjusted accordingly…but still getting WA for some test case…Can you visualise any such case?
CodeChef: Practical coding for everyone .
MW it passed the <<> case
ambarpal:
<<>><<<>>
///maybe this is what you asked
#include <bits/stdc++.h>
#include
#include
#define ll long long int
using namespace std;
bool func(string s,int i,int j)
{
stack<char> stk;
for(;i<=j;i++)
{
if(s[i]=='<')
stk.push(s[i]);
else
{ if(stk.empty()||stk.top()!='<')
return false;
else
stk.pop();
}
}
return stk.empty();
}
int main() {
ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
int t;cin>>t;
while(t–)
{
string s;
cin>>s;
stack stk;
vector v;
for(int i=0;i<s.length();i++)
{
if(s[i]=='<')
{
for(int j=i+1;j<s.length();j++)
{
if(s[j]=='>')
{
if(func(s,i,j)==true)////if(func(s,i+1,j-1)==true)
v.push_back(j-i+1);
}
}
}
}
if(v.size()==0)
cout<<"0\n";
else
cout<<*max_element(v.begin(),v.end())<<"\n";
}
}
shebz
May 9, 2020, 7:10am
79
Can anyone please explain what is longest prefix length means it’s confusing please break it in simple terms.
Thanks
1 Like
Can anyone tell me why this is not working?
#include <iostream>
using namespace std;
int main()
{
int t;cin>>t;
while(t--)
{
string s;
cin>>s;
int open=0,num=0;
for(int i=0;i<s.length();i++)
{
if(s[i]=='<')
{
open++;
}
else
{
if(open>0)
{
open--;
num++;
}
}
}
cout<<num*2<<endl;
}
}
ssjgz:
<><
can any one tell me why i am getting a WA