From ff0eb06f132a3e7b464219bc3e94ca60feb41157 Mon Sep 17 00:00:00 2001
From: Madhav <madhavgaba2@gmail.com>
Date: Tue, 29 Aug 2017 15:04:30 +0530
Subject: [PATCH] segment tree with lazy propagation

---
 Range queries/segTree.cpp | 90 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 Range queries/segTree.cpp

diff --git a/Range queries/segTree.cpp b/Range queries/segTree.cpp
new file mode 100644
index 000000000..594c2791e
--- /dev/null
+++ b/Range queries/segTree.cpp	
@@ -0,0 +1,90 @@
+#include <bits/stdc++.h>
+#define MAX 4000000
+using namespace std;
+typedef long long ll;
+void ConsTree(ll arr[],ll segtree[],ll low,ll high,ll pos)
+{
+	if(low == high)
+	{
+		segtree[pos] = arr[low];
+		return;
+	}
+	ll mid = (low+high)/2;
+	ConsTree(arr,segtree,low,mid,2*pos+1);
+	ConsTree(arr,segtree,mid+1,high,2*pos+2);
+	segtree[pos] = segtree[2*pos+1] + segtree[2*pos+2];
+}
+ll query(ll segtree[],ll lazy[],ll qlow,ll qhigh,ll low,ll high,ll pos)
+{
+	if(low > high)
+		return 0;
+	if(qlow>high || qhigh<low)
+		return 0;
+	if(lazy[pos] != 0)
+	{
+		segtree[pos] += lazy[pos]*(high-low+1);
+		if(low != high)
+		{
+			lazy[2*pos+1] += lazy[pos];
+			lazy[2*pos+2] += lazy[pos];
+		}
+		lazy[pos] = 0;
+	}
+	if(qlow<=low && qhigh>=high)
+		return segtree[pos];
+		ll mid = (low+high)/2;
+	return query(segtree,lazy,qlow,qhigh,low,mid,2*pos+1) + query(segtree,lazy,qlow,qhigh,mid+1,high,2*pos+2);
+}
+void update(ll segtree[],ll lazy[],ll start,ll end,ll delta,ll low,ll high,ll pos)
+{
+	if(low>high)
+		return;
+	if(lazy[pos] != 0)
+	{
+		segtree[pos] += lazy[pos]*(high-low+1);
+		if(low!=high)
+		{
+			lazy[2*pos+1] += lazy[pos];
+			lazy[2*pos+2] += lazy[pos];
+		}
+		lazy[pos] = 0;
+	}
+	if(start > high || end < low)
+		return;
+	if(start <= low && end >= high)
+	{
+		segtree[pos] += delta*(high-low+1);
+		if(low != high)
+		{
+			lazy[2*pos+1] += delta;
+			lazy[2*pos+2] += delta;
+		}
+		return;
+	}
+	ll mid = (low+high)/2;
+	update(segtree,lazy,start,end,delta,low,mid,2*pos+1);
+	update(segtree,lazy,start,end,delta,mid+1,high,2*pos+2);
+	segtree[pos] = segtree[2*pos+1] + segtree[2*pos+2];
+}
+int main() {
+		ll n,c;
+		scanf("%lld %lld",&n,&c);
+		ll arr[n]={0},p,q,v,choice;
+		ll segtree[MAX],lazy[MAX]={0};
+		ConsTree(arr,segtree,0,n-1,0);
+		while(c--)
+		{
+			scanf("%lld",&choice);
+			if(choice == 0)
+			{
+				scanf("%lld %lld %lld",&p,&q,&v);
+				update(segtree,lazy,p-1,q-1,v,0,n-1,0);
+			}
+			else
+			{
+				scanf("%lld %lld",&p,&q);
+				printf("%lld\n",query(segtree,lazy,p-1,q-1,0,n-1,0));
+			}
+		}
+	return 0;
+}