RMQ with update without Lazy
RMQSQ - Range Minimum Query with update
#include<bits/stdc++.h>
using namespace std;
int tre[1000000],a[1000000];
void build_tree(int in,int st,int en)
{
if(st>en)
return ;
if(st==en)
{
tre[in]=a[st];
return ;
}
else
{
build_tree(2*in,st,(st+en)/2);
build_tree(2*in+1,(st+en)/2+1,en);
tre[in]=tre[2*in]+tre[2*in+1];
}
}
int query(int node,int st,int en,int fs,int fe)
{
if(fe<st || fs>en || fs>fe)
return 0;
if(fs<=st && fe>=en)
{
return tre[node];
}
else
{
return query(2*node,st,(st+en)/2,fs,fe)+query(1+2*node,1+(st+en)/2,en,fs,fe) ;
}
}
void update(int node,int st,int en,int fs,int fe,int sum)
{
if(fe<st || fs>en || fs>fe)
return ;
if(st==en) /// update will occur at the leaf
tre[node]+=sum;
if(st!=en)
{
update(2*node,st,(st+en)/2,fs,fe,sum);
update(2*node+1,1+(st+en)/2,en,fs,fe,sum);
tre[node]=tre[2*node]+tre[2*node+1];
}
}
int main()
{
int t;
cin>>t;
while(t--)
{
for(int i=0;i<1000000;i++){a[i]=0; tre[i]=0;}
int n,i,ty,sum,q,l,r;;
cin>>n;
for(i=0;i<n;i++)
a[i]=0;
build_tree(1,0,n-1); /// tree is to be built and minimum given to 1th index
//for(i=1;i<2*n;i++)
//cout<<tre[i]<<" ";
cin>>q;
for(i=0;i<q;i++)
{
cin>>ty;
if(ty==1)
{
cin>>l>>r;
l--; r--;
cout<<query(1,0,n-1,l,r)<<endl; /// starting ur query , start looking ur range (l,r) from the 1st node of tree whose range is(0,n-1)
}
else
{
cin>>l>>r>>sum;
l--; r--;
update(1,0,n-1,l,r,sum);
//for(i=1;i<2*n;i++)
//cout<<tre[i]<<" ";
}
}
}
return 0;
}
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