added segment tree code with some basic problems

Add Code Here/C++/segment_tree/build_query.cpp

@@ -0,0 +1,123 @@
+#include <bits/stdc++.h>
+#define ll long long 
+#define int long long 
+#define MOD1 998244353
+#define INF 1e18
+#define endl "\n"
+#define vi vector<int>
+#define pb push_back
+#define vvi vector<vector<int>>
+#define pii pair<int, int>
+#define ff first
+#define ss second
+#define ss second
+#define PI 3.141592653589793238462
+#define set_bits __builtin_popcountll
+#define sz(x) ((int)(x).size())
+#define all(x) (x).begin(), (x).end()
+#define f(i,a,b) for(ll i=a;i<b;i++)
+
+using namespace std;
+
+class SGTree {
+	vector<int> seg;
+public:
+	SGTree(int n) {
+		seg.resize(4 * n + 1);
+	}
+
+	void build(int ind, int low, int high, int arr[]) {
+		if (low == high) {
+			seg[ind] = arr[low];
+			return;
+		}
+
+		int mid = (low + high) / 2;
+		build(2 * ind + 1, low, mid, arr);
+		build(2 * ind + 2, mid + 1, high, arr);
+		seg[ind] = min(seg[2 * ind + 1], seg[2 * ind + 2]);
+	}
+
+	int query(int ind, int low, int high, int l, int r) {
+		// no overlap
+		// l r low high or low high l r
+		if (r < low || high < l) return INT_MAX;
+
+		// complete overlap
+		// [l low high r]
+		if (low >= l && high <= r) return seg[ind];
+
+		int mid = (low + high) >> 1;
+		int left = query(2 * ind + 1, low, mid, l, r);
+		int right = query(2 * ind + 2, mid + 1, high, l, r);
+		return min(left, right);
+	}
+
+	void update(int ind, int low, int high, int i, int val) {
+		if (low == high) {
+			seg[ind] = val;
+			return;
+		}
+
+		int mid = (low + high) >> 1;
+		if (i <= mid) update(2 * ind + 1, low, mid, i, val);
+		else update(2 * ind + 2, mid + 1, high, i, val);
+		seg[ind] = min(seg[2 * ind + 1], seg[2 * ind + 2]);
+	}
+};
+
+
+#define watch(x) cout << (#x) << " = " << (x) << endl
+const int MOD = 1e9 + 7;
+ll gcd(ll a, ll b) {if (b > a) {return gcd(b, a);} if (b == 0) {return a;} return gcd(b, a % b);}
+ll mult(ll x, ll y) {ll res = x * y;return (res >= MOD ? res % MOD : res);}
+ll factorial(ll v){ll ans=1;for(int i=2;i<=v;i++){ans*=i;ans%=MOD;}return ans;}
+ll power(ll x, ll y){   if (y < 0)return 1;ll res = 1; x %= MOD;while (y!=0) {if ((y & 1)==1)res = mult(res, x); y >>= 1;x = mult(x, x);} return res;}
+vector<ll> sieve(int n) {int*arr = new int[n + 1](); vector<ll> vect; for (int i = 2; i <= n; i++)if (arr[i] == 0) {vect.push_back(i); for (int j = 2 * i; j <= n; j += i)arr[j] = 1;} return vect;}
+void vin( vector<int> &v , int n ){for (int i = 0; i < n; i++){int x ;cin >> x; v.push_back(x);}}
+void vout(vector<int> &v){for (int i = 0; i < v.size(); i++){cout << v[i] << " " ;}cout << endl;}
+ll highestPowerof2(ll n){ ll p = (ll)log2(n);   return (ll)pow(2, p);}
+bool isPowerOfTwo(int n){ if(n==0)   return false;   return (ceil(log2(n)) == floor(log2(n)));}
+bool chkprime(int n){ for(int i = 2 ; i*i <= n ; i++){ if( n % i == 0) return false;} return true; }
+string to_binary(int n) { string s = ""; for (int i = 31; i >= 0; i--) { int k = n >> i; if (k & 1) s = s + "1";else s = s + "0";}return s ; }
+static void removeTrailingCharacters(std::string &str, const char charToRemove) {str.erase (str.find_last_not_of(charToRemove) + 1, std::string::npos );}
+static void removeLeadingCharacters(std::string &str, const char charToRemove) {str.erase(0, std::min(str.find_first_not_of(charToRemove), str.size() - 1));}
+long long lcm(int a, int b){    return (a / gcd(a, b)) * b;}
+
+
+
+void prakhar() {
+
+    int n ;
+    cin  >> n ; 
+    int arr[n];
+    for (int i = 0; i < n; i++)
+    {
+        cin >> arr[i];
+    }
+    SGTree sgt(n);
+    sgt.build(0, 0 , n - 1 , arr);
+
+    cout << sgt.query(0, 0 , n - 1 , 2, n -1);
+
+
+
+}
+
+int32_t main() {
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    #ifndef ONLINE_JUDGE
+    freopen("input.txt", "r", stdin);
+    freopen("output.txt", "w", stdout);
+    freopen("error.txt", "w", stderr);
+    #endif
+    ll t = 1 ;
+    // cin >> t ;
+    for (int i = 0; i < t; i++) {
+        prakhar();
+    }
+
+    return 0;
+
+}

Add Code Here/C++/segment_tree/dynamic_range_sum.cpp

@@ -0,0 +1,141 @@
+#include <bits/stdc++.h>
+#define ll long long 
+#define int long long 
+#define MOD1 998244353
+#define INF 1e18
+#define endl "\n"
+#define vi vector<int>
+#define vii vector<pair<int, int>>
+#define vs vector<string>
+#define vc vector<char>ṇ
+#define vb vector<bool>
+#define pb push_back
+#define vvi vector<vector<int>>
+#define pii pair<int, int>
+#define ff first
+#define ss second
+#define ss second
+#define PI 3.141592653589793238462
+#define set_bits __builtin_popcountll
+#define sz(x) ((int)(x).size())
+#define all(x) (x).begin(), (x).end()
+#define f(i,a,b) for(ll i=a;i<b;i++)
+
+using namespace std;
+
+class SGTree {
+	vector<int> seg;
+public:
+	SGTree(int n) {
+		seg.resize(4 * n + 1);
+	}
+
+	void build(int ind, int low, int high, int arr[]) {
+		if (low == high) {
+			seg[ind] = arr[low];
+			return;
+		}
+
+		int mid = (low + high) / 2;
+		build(2 * ind + 1, low, mid, arr);
+		build(2 * ind + 2, mid + 1, high, arr);
+		seg[ind] = seg[2 * ind + 1] + seg[2 * ind + 2];
+
+        // cout << seg << endl;
+	}
+
+	int query(int ind, int low, int high, int l, int r) {
+		// no overlap
+		// l r low high or low high l r
+		if (r < low || high < l) return 0;
+
+		// complete overlap
+		// [l low high r]
+		if (low >= l && high <= r) return seg[ind];
+
+		int mid = (low + high) >> 1;
+		int left = query(2 * ind + 1, low, mid, l, r);
+		int right = query(2 * ind + 2, mid + 1, high, l, r);
+		return (left+right);
+	}
+	void update(int ind, int low, int high, int i, int val) {
+		if (low == high) {
+			seg[ind] = val;
+			return;
+		}
+
+		int mid = (low + high) >> 1;
+		if (i <= mid) update(2 * ind + 1, low, mid, i, val);
+		else update(2 * ind + 2, mid + 1, high, i, val);
+		seg[ind] = seg[2 * ind + 1] + seg[2 * ind + 2];
+	}
+};
+
+
+#define watch(x) cout << (#x) << " = " << (x) << endl
+const int MOD = 1e9 + 7;
+ll gcd(ll a, ll b) {if (b > a) {return gcd(b, a);} if (b == 0) {return a;} return gcd(b, a % b);}
+ll mult(ll x, ll y) {ll res = x * y;return (res >= MOD ? res % MOD : res);}
+ll factorial(ll v){ll ans=1;for(int i=2;i<=v;i++){ans*=i;ans%=MOD;}return ans;}
+ll power(ll x, ll y){   if (y < 0)return 1;ll res = 1; x %= MOD;while (y!=0) {if ((y & 1)==1)res = mult(res, x); y >>= 1;x = mult(x, x);} return res;}
+vector<ll> sieve(int n) {int*arr = new int[n + 1](); vector<ll> vect; for (int i = 2; i <= n; i++)if (arr[i] == 0) {vect.push_back(i); for (int j = 2 * i; j <= n; j += i)arr[j] = 1;} return vect;}
+void vin( vector<int> &v , int n ){for (int i = 0; i < n; i++){int x ;cin >> x; v.push_back(x);}}
+void vout(vector<int> &v){for (int i = 0; i < v.size(); i++){cout << v[i] << " " ;}cout << endl;}
+ll highestPowerof2(ll n){ ll p = (ll)log2(n);   return (ll)pow(2, p);}
+bool isPowerOfTwo(int n){ if(n==0)   return false;   return (ceil(log2(n)) == floor(log2(n)));}
+bool chkprime(int n){ for(int i = 2 ; i*i <= n ; i++){ if( n % i == 0) return false;} return true; }
+string to_binary(int n) { string s = ""; for (int i = 31; i >= 0; i--) { int k = n >> i; if (k & 1) s = s + "1";else s = s + "0";}return s ; }
+static void removeTrailingCharacters(std::string &str, const char charToRemove) {str.erase (str.find_last_not_of(charToRemove) + 1, std::string::npos );}
+static void removeLeadingCharacters(std::string &str, const char charToRemove) {str.erase(0, std::min(str.find_first_not_of(charToRemove), str.size() - 1));}
+long long lcm(int a, int b){    return (a / gcd(a, b)) * b;}
+
+
+
+void prakhar() {
+
+    int n,  q ;
+    cin  >> n >> q ; 
+    int arr[n];
+    for (int i = 0; i < n; i++)
+    {
+        cin >> arr[i];
+    }
+
+    SGTree sgt(n);
+    sgt.build(0, 0 , n - 1 , arr);
+
+
+    for (int i = 0; i < q; i++)
+    {
+        int c, l , r ;
+        cin >> c >> l >> r ;
+		if( c == 1)
+		{
+			sgt.update(0, 0, n-1, --l, r );
+		}
+		else
+        cout << sgt.query(0, 0, n-1, --l , --r ) << endl;
+
+    }
+
+
+
+}
+
+int32_t main() {
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    #ifndef ONLINE_JUDGE
+    freopen("input.txt", "r", stdin);
+    freopen("output.txt", "w", stdout);
+    freopen("error.txt", "w", stderr);
+    #endif
+    ll t = 1 ;
+    // cin >> t ;
+    for (int i = 0; i < t; i++) {
+        prakhar();
+    }
+
+    return 0;
+
+}