diff --git a/oct-6.cpp b/oct-6.cpp
new file mode 100644
index 0000000..93a13ba
--- /dev/null
+++ b/oct-6.cpp
@@ -0,0 +1,303 @@
+#include <bits/stdc++.h>
+#define ll long long int
+using namespace std;
+
+ll maxDigit(string s) {
+    ll mx = 0;
+    for(ll i = 0 ; i < s.size() ; i++) {
+        if(s[i] >= '0' && s[i] <= '9') {
+            ll v = s[i] - 48;
+            mx = max(mx , v);
+        }
+        else{
+            ll v = s[i] - 55;
+            mx = max(mx , v);
+        }
+    }
+    return mx;
+}
+
+ll calcnz (string s , ll b) {
+    ll digit = 0;
+    ll ans = 0;
+    ll po = s.size() - 1;
+    ll j = 0;
+    for(ll i = po; i >= 0; i--) {
+        if(s[i] >= '0' && s[i] <='9') {
+            digit = s[i] - 48;
+        }
+        else{
+            digit = s[i] - 65 + 10;
+        }
+
+        ll p = pow(b , j);
+        j++;
+        ans += (p * digit);
+    }
+    return ans;
+}
+
+ll calc (string s , ll b , ll start) {
+    if(b < start) {
+        return -1;
+    }
+
+    ll digit = 0;
+    ll ans = 0;
+    ll po = s.size() - 1;
+    ll j = 0;
+
+    for(ll i = po; i >= 0; i--) {
+        if(s[i] >= '0' && s[i] <= '9') {
+            digit = s[i] - 48;
+        }
+        else{
+            digit = s[i] - 55;
+        }
+
+        ll p = pow(b , j);
+        if(p < 0) {
+            return -1;
+        }
+        j++;
+        ans += (p * digit);
+        if(ans > 1000000000000) {
+            return -1;
+        }
+    }
+    if(ans < 0) {
+        return -1;
+    }
+    return ans;
+}
+
+int main(){
+    ll t;
+    cin >> t;
+    while(t--) {
+        ll n;
+        cin >> n;
+        ll temp = n;
+        vector< pair <ll , string> > v;
+        while (temp--) {
+            ll base;
+            string str;
+            cin >> base >> str;
+            v.push_back(make_pair(base , str));
+        }
+
+        ll sze  = v.size();
+        ll flag = 0;
+
+        vector < pair <ll , string> > non_zero;
+
+        for (ll i = 0 ; i < sze; i++) {
+            if(v[i].first != -1) {
+                flag = 1;
+                non_zero.push_back(make_pair(v[i].first , v[i].second));
+            }
+        }
+
+        ll ans = 0;
+
+
+        vector <ll> values;
+        if(non_zero.size()) {
+            for(ll i = 0; i < non_zero.size() ; i++) {
+                ll inter = calcnz(non_zero[i].second , non_zero[i].first);
+                values.push_back(inter);
+            }
+        }
+
+
+        if(values.size() > 1) {
+            ll real = 0;
+            for(ll i = 1 ; i < values.size() ; i++) {
+                if(values[i] != values[i-1]) {
+                    real = 1;
+                }
+            }
+            if(real) {
+                cout << -1 << endl;
+                continue;
+            }
+            else{
+                ans = values[0];
+            }
+        }
+        else{
+            if(values.size()) {
+                ans = values[0];
+            }
+        }
+
+        if(flag) {
+            ll arr[n][37];
+            for(ll i = 0; i < n ; i++){
+                for(ll j = 0 ; j < 37 ; j++) {
+                    arr[i][j] = 0;
+                }
+            }
+
+            for(ll i = 0 ; i < n ; i++) {
+                ll start = maxDigit(v[i].second) + 1;
+                for(ll j = 2 ; j <= 36 ; j++ ) {
+                    ll store = 0;
+
+                    string str = v[i].second;
+
+                    store = calc (str , j , start);
+                    arr[i][j] = store;
+                    store = 0;
+                }
+            }
+
+
+            ll breaker = 0;
+            ll finalstatus = 0;
+            for (ll i = 0; i < n ; i++) {
+                breaker = 0;
+                for (ll j = 2 ; j <= 36 ; j++) {
+                    if(ans == arr[i][j]) {
+                        breaker = 1;
+                        break;
+                    }
+                }
+                if(breaker == 1) {
+                    continue;
+                }
+                else{
+                    finalstatus = 1;
+                    break;
+                }
+            }
+
+            if(finalstatus) {
+                cout << -1 << endl;
+            }
+            else{
+                cout << ans << endl;
+            }
+        }
+        else {
+            ll arr[n][37];
+            for(ll i = 0; i < n ; i++){
+                for(ll j = 0 ; j < 37 ; j++) {
+                    arr[i][j] = 0;
+                }
+            }
+
+            for(ll i = 0 ; i < n ; i++) {
+                ll start = maxDigit(v[i].second) + 1;
+                for(ll j = 2 ; j <= 36 ; j++) {
+                    ll store = 0;
+
+                    string str = v[i].second;
+
+                    store = calc(str , j , start);
+                    arr[i][j] = store;
+
+                    store = 0;
+                }
+            }
+
+            // for(ll i = 0; i < n ; i++){
+            //     for(ll j = 2 ; j <= 36 ; j++) {
+            //         cout << arr[i][j] << " ";
+            //     }
+            //     cout<<endl;
+            // }
+            // cout << endl;
+
+            unordered_map <ll , ll> x;
+            unordered_map <ll , ll> final;
+            unordered_map <ll ,ll> :: iterator itr;
+
+            for(ll i = 2 ; i < 37 ; i++) {
+                if(arr[0][i] != -1) {
+                    x[arr[0][i]] = 1;
+                }
+            }
+
+            if(x.size() == 0) {
+                cout<< -1 <<endl;
+                continue;
+            }
+
+            flag = 0;
+            for(ll i = 1 ; i < n ; i++) {
+                for(ll j = 2 ; j < 37 ; j++) {
+                    if(arr[i][j] != -1) {
+                        if(x[arr[i][j]]) {
+                            final[arr[i][j]] = 1;
+                        }
+                    }
+                }
+
+                if(final.size() == 0) {
+                    flag = 1;
+                    break;
+                }
+
+                x.clear();
+                for(itr = final.begin() ; itr != final.end() ; itr++) {
+                    x[itr -> first] = 1;
+                }
+                final.clear();
+            }
+
+
+            if(flag) {
+                cout << -1 << endl;
+                continue;
+            }
+
+            ll mn = 1000000000000;
+            map <ll,ll> mp;
+            for(itr = x.begin() ; itr != x.end() ; itr++) {
+                ll v = itr -> first;
+                if(mn > v) {
+                    mn = v;
+                }
+                mp[v] = 1;
+            }
+            // cout << mn << endl ;
+            map <ll , ll> :: iterator it;
+            for(it = mp.begin() ; it != mp.end() ; it++) {
+                cout << it -> first << endl;
+                break;
+            }
+        }
+    }
+    return 0;
+}
+
+
+
+
+// string s = v[index].second;
+// ll b = v[index].first;
+//
+// ans = calc (s , b , 0);
+
+// if(ans == -1) {
+//     cout << -1 <<endl;
+//     continue;
+// }
+
+// cout << ans <<endl;
+
+
+// for(ll i = 0; i < n ; i++){
+    //     for(ll j = 2 ; j <= 36 ; j++) {
+        //         cout << arr[i][j] << " ";
+        //     }
+        //     cout<<endl;
+        // }
+
+
+
+                // for(ll i = 0 ; i < values.size() ; i++) {
+                //     cout << values[i] << " ";
+                // }
+                // cout << endl;
diff --git a/pairsum2.cpp b/pairsum2.cpp
new file mode 100644
index 0000000..a71ea3c
--- /dev/null
+++ b/pairsum2.cpp
@@ -0,0 +1,45 @@
+#include <bits/stdc++.h>
+#define ll long long
+using namespace std;
+int main(){
+	ll t;
+	cin t;
+	cin>>t;
+	while(t--){
+		ll n,q;
+		cin>>n>>q;
+		ll arr[n-1] = {0};
+		for(ll i=0;i<n-1;i++){
+			cin>>arr[i];
+		}
+		while(q--){
+			ll a,b;
+			ll diff = abs(a - b);
+			if(diff%2 == 1){
+				ll mx = max(a,b);
+				ll mn = min(a,b);
+				mx--;
+				mn--;
+				cout<<mn<<" "<<mx<<endl;
+				ll temp = arr[mn-1];
+				cout<<temp<<endl;
+				ll count = 0;
+				for(ll i=mn;i<mx-1;i++){
+					if(count%2 == 0){
+						temp -= arr[i];
+					}
+					else{
+						temp += arr[i];
+					}
+				}
+				cout<<temp<<endl;
+			}
+			else{
+				cout<<"UNKNOWN"<<endl;
+			}
+ 		}
+	}
+	return 0;
+}
+
+