I was attempting the E problem of round #878 Div 3. I am getting TLE in my code but it seems to me that the Time complexity of the code if _O(T * (t + q))_ which should get accepted. Please tell me the mistake in the code. ↵
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**Approach**: I am storing the position which are unblocked at time (relative to current time) in a queue. The string a and b are just a copy of s1 and s2 which will be blocked and unblocked throughout the process (s1 and s2 are not altered). ↵
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Problem: [Div 3 E](https://mirror.codeforces.com/contest/1840/problem/E) ↵
My submission: [Submission](https://mirror.codeforces.com/contest/1840/submission/208859532)↵
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<spoiler summary="Code">↵
↵
~~~~~↵
#include <bits/stdc++.h>↵
#define rep(i, n) for (long long i = 0; i < n; ++i)↵
#define coutyes cout << "YES" << nl↵
#define coutno cout << "NO" << nl↵
#define IOS \↵
ios_base::sync_with_stdio(0); \↵
cin.tie(0); \↵
cout.tie(0)↵
#define nl '\n'↵
using namespace std;↵
using ll = long long;↵
↵
void solve()↵
{↵
string a, b, s1, s2; cin >> s1 >> s2;↵
a = s1, b = s2;↵
ll t, q; cin >> t >> q;↵
queue<ll> qu;↵
rep(i,t) qu.push(-1);↵
while(q--){↵
ll x; cin >> x;↵
↵
if(qu.front()==-1) qu.pop();↵
else{↵
ll k=qu.front();↵
a[k]=s1[k], b[k]=s2[k];↵
qu.pop();↵
}↵
↵
if(x==3){↵
qu.push(-1);↵
if(a==b)coutyes;↵
else coutno;↵
}↵
else if(x==2){↵
qu.push(-1);↵
ll p, q, r, s; cin >> p >> q >> r >> s;↵
if(p==1 && r==1)↵
swap(a[q - 1], a[s - 1]), swap(s1[q - 1], s1[s - 1]);↵
else if(p==1 && r==2)↵
swap(a[q - 1], b[s - 1]), swap(s1[q - 1], s2[s - 1]);↵
else if(p==2 && r==1)↵
swap(b[q - 1], a[s - 1]), swap(s2[q - 1], s1[s - 1]);↵
else↵
swap(b[q - 1], b[s - 1]), swap(s2[q - 1], s2[s - 1]);↵
}↵
else{↵
ll y; cin>>y;↵
qu.push(y - 1); a[y-1]='A'; b[y-1]='A';↵
}↵
} ↵
}↵
signed main()↵
{↵
IOS;↵
int t=1; cin >> t;↵
while(t--) solve();↵
}↵
~~~~~↵
↵
↵
</spoiler>↵
↵
↵
**Approach**: I am storing the position which are unblocked at time (relative to current time) in a queue. The string a and b are just a copy of s1 and s2 which will be blocked and unblocked throughout the process (s1 and s2 are not altered). ↵
↵
Problem: [Div 3 E](https://mirror.codeforces.com/contest/1840/problem/E) ↵
My submission: [Submission](https://mirror.codeforces.com/contest/1840/submission/208859532)↵
↵
↵
↵
<spoiler summary="Code">↵
↵
~~~~~↵
#include <bits/stdc++.h>↵
#define rep(i, n) for (long long i = 0; i < n; ++i)↵
#define coutyes cout << "YES" << nl↵
#define coutno cout << "NO" << nl↵
#define IOS \↵
ios_base::sync_with_stdio(0); \↵
cin.tie(0); \↵
cout.tie(0)↵
#define nl '\n'↵
using namespace std;↵
using ll = long long;↵
↵
void solve()↵
{↵
string a, b, s1, s2; cin >> s1 >> s2;↵
a = s1, b = s2;↵
ll t, q; cin >> t >> q;↵
queue<ll> qu;↵
rep(i,t) qu.push(-1);↵
while(q--){↵
ll x; cin >> x;↵
↵
if(qu.front()==-1) qu.pop();↵
else{↵
ll k=qu.front();↵
a[k]=s1[k], b[k]=s2[k];↵
qu.pop();↵
}↵
↵
if(x==3){↵
qu.push(-1);↵
if(a==b)coutyes;↵
else coutno;↵
}↵
else if(x==2){↵
qu.push(-1);↵
ll p, q, r, s; cin >> p >> q >> r >> s;↵
if(p==1 && r==1)↵
swap(a[q - 1], a[s - 1]), swap(s1[q - 1], s1[s - 1]);↵
else if(p==1 && r==2)↵
swap(a[q - 1], b[s - 1]), swap(s1[q - 1], s2[s - 1]);↵
else if(p==2 && r==1)↵
swap(b[q - 1], a[s - 1]), swap(s2[q - 1], s1[s - 1]);↵
else↵
swap(b[q - 1], b[s - 1]), swap(s2[q - 1], s2[s - 1]);↵
}↵
else{↵
ll y; cin>>y;↵
qu.push(y - 1); a[y-1]='A'; b[y-1]='A';↵
}↵
} ↵
}↵
signed main()↵
{↵
IOS;↵
int t=1; cin >> t;↵
while(t--) solve();↵
}↵
~~~~~↵
↵
↵
</spoiler>↵
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