added 2000 A,B,C

Codes/2000 A - Primary Task/2000A.cpp

@@ -0,0 +1,58 @@
+#include <bits/stdc++.h>
+using namespace std;
+#ifdef ONLINE_JUDGE
+#define dbg(...)
+#else
+#include "Assets/debug.h"
+#endif
+#define  int  long long
+#define  ll  long long
+#define  endl  '\n'
+#define  ff  first
+#define  ss  second
+#define  ins  insert
+#define  pb  push_back
+#define  ppb  pop_back
+#define  sz(x)  (int)(x).size()
+#define  all(x)  x.begin(), x.end()
+#define  rep(i,a,b)  for(int i=a; i<b; ++i)
+#define  rrep(i,a,b) for(int i=a; i>=b; --i)
+#define  yn(f)  f? cout<<"YES\n":cout<<"NO\n"
+#define  FAST  (ios_base::sync_with_stdio(false), cin.tie(nullptr));
+ll pow(ll x,ll y,ll m=1e9+7) {ll ans=1;x%=m;while(y){if(y&1)ans=(ans*x)%m;x=(x*x)%m;y>>=1;}return ans;}
+
+void solve()
+{
+    string s;
+    cin>>s;
+    if(sz(s)<3)
+    {
+        yn(0);
+    }
+    else if(s[0]=='1' && s[1]=='0')
+    {
+        if(s[2]=='0')   yn(0);
+        else 
+        {
+            string t=s;
+            t.erase(t.begin());
+            t.erase(t.begin());
+            int n=stoi(t);
+            dbg(n);
+            yn(n>1);
+        }
+    }
+    else yn(0);
+}
+
+signed main()
+{
+    FAST;
+    int TCS = 1;
+    cin >> TCS;
+    for (int TC = 1; TC <= TCS; ++TC)
+    {
+      // cout<<"Case "<<TC<<": ";
+      solve();
+    }
+}

Codes/2000 B - Seating in a Bus/2000B.cpp

@@ -0,0 +1,55 @@
+#include <bits/stdc++.h>
+using namespace std;
+#ifdef ONLINE_JUDGE
+#define dbg(...)
+#else
+#include "Assets/debug.h"
+#endif
+#define  int  long long
+#define  ll  long long
+#define  endl  '\n'
+#define  ff  first
+#define  ss  second
+#define  ins  insert
+#define  pb  push_back
+#define  ppb  pop_back
+#define  sz(x)  (int)(x).size()
+#define  all(x)  x.begin(), x.end()
+#define  rep(i,a,b)  for(int i=a; i<b; ++i)
+#define  rrep(i,a,b) for(int i=a; i>=b; --i)
+#define  yn(f)  f? cout<<"YES\n":cout<<"NO\n"
+#define  FAST  (ios_base::sync_with_stdio(false), cin.tie(nullptr));
+ll pow(ll x,ll y,ll m=1e9+7) {ll ans=1;x%=m;while(y){if(y&1)ans=(ans*x)%m;x=(x*x)%m;y>>=1;}return ans;}
+
+void solve()
+{
+    int n;
+    cin>>n;
+    vector<int>v(n);
+    for(auto &i:v)  cin>>i;
+    map<int,int>m;
+    m[v[0]]++;
+    rep(i,1,n)
+    {
+        dbg(m);
+        if(m[v[i]-1]==0 && m[v[i]+1]==0)
+        {
+            yn(0);
+            return;
+        }
+        m[v[i]]++;
+    }
+    yn(1);
+}
+
+signed main()
+{
+    FAST;
+    int TCS = 1;
+    cin >> TCS;
+    for (int TC = 1; TC <= TCS; ++TC)
+    {
+      // cout<<"Case "<<TC<<": ";
+      solve();
+    }
+}

Codes/2000 C - Numeric String Template/2000C.cpp

@@ -0,0 +1,72 @@
+#include <bits/stdc++.h>
+using namespace std;
+#ifdef ONLINE_JUDGE
+#define dbg(...)
+#else
+#include "Assets/debug.h"
+#endif
+#define  int  long long
+#define  ll  long long
+#define  endl  '\n'
+#define  ff  first
+#define  ss  second
+#define  ins  insert
+#define  pb  push_back
+#define  ppb  pop_back
+#define  sz(x)  (int)(x).size()
+#define  all(x)  x.begin(), x.end()
+#define  rep(i,a,b)  for(int i=a; i<b; ++i)
+#define  rrep(i,a,b) for(int i=a; i>=b; --i)
+#define  yn(f)  f? cout<<"YES\n":cout<<"NO\n"
+#define  FAST  (ios_base::sync_with_stdio(false), cin.tie(nullptr));
+ll pow(ll x,ll y,ll m=1e9+7) {ll ans=1;x%=m;while(y){if(y&1)ans=(ans*x)%m;x=(x*x)%m;y>>=1;}return ans;}
+
+void solve()
+{
+    int n, m;
+    cin >> n;
+    vector<int> a(n);
+    for(auto &i:a)    cin >>i;
+    cin >> m;
+    while(m--)
+    {
+        string s;
+        cin >> s;
+        if (s.size() != n) 
+        {
+            yn(0);
+            continue;
+        }
+        map<char, int> char_to_num;
+        map<int, char> num_to_char;
+        bool f = 1;
+        for (int j = 0; j < n; ++j) 
+        {
+            char c = s[j];
+            int num = a[j];
+            if (char_to_num.count(c) && char_to_num[c] != num) {
+                f = 0;
+                break;
+            }
+            if (num_to_char.count(num) && num_to_char[num] != c) {
+                f = 0;
+                break;
+            }
+            char_to_num[c] = num;
+            num_to_char[num] = c;
+        }
+        yn(f);
+    }
+}
+
+signed main()
+{
+    FAST;
+    int TCS = 1;
+    cin >> TCS;
+    for (int TC = 1; TC <= TCS; ++TC)
+    {
+      // cout<<"Case "<<TC<<": ";
+      solve();
+    }
+}

Readme.md

@@ -387,6 +387,9 @@ This repository contains my solutions of Codeforces problems. They are in C++ la
 | 375 | 1999 B | Card Game | [Question](https://codeforces.com/problemset/problem/1999/B) | [Solution](https://github.com/ShazidMashrafi/Codeforces-Solutions/tree/master/Codes/1999%20B%20-%20Card%20Game)
 | 376 | 1999 C | Showering | [Question](https://codeforces.com/problemset/problem/1999/C) | [Solution](https://github.com/ShazidMashrafi/Codeforces-Solutions/tree/master/Codes/1999%20C%20-%20Showering)
 | 377 | 1999 D | Slavic's Exam | [Question](https://codeforces.com/problemset/problem/1999/D) | [Solution](https://github.com/ShazidMashrafi/Codeforces-Solutions/tree/master/Codes/1999%20D%20-%20Slavic's%20Exam)
+| 378 | 2000 A | Primary Task | [Question](https://codeforces.com/problemset/problem/2000/A) | [Solution](https://github.com/ShazidMashrafi/Codeforces-Solutions/tree/master/Codes/2000%20A%20-%20Primary%20Task)
+| 379 | 2000 B | Seating in a Bus | [Question](https://codeforces.com/problemset/problem/2000/B) | [Solution](https://github.com/ShazidMashrafi/Codeforces-Solutions/tree/master/Codes/2000%20B%20-%20Seating%20in%20a%20Bus)
+| 380 | 2000 C | Numeric String Template | [Question](https://codeforces.com/problemset/problem/2000/C) | [Solution](https://github.com/ShazidMashrafi/Codeforces-Solutions/tree/master/Codes/2000%20C%20-%20Numeric%20String%20Template)