1881G - Anya and the Mysterious String - CodeForces Solution

#include<iostream>
#include<algorithm>
#include<cmath>
#include<vector>
#include<queue>
#include<cstring>
#include<map>
#include<bitset>
#include<set>
using namespace std;
#define LL long long  
#define PLL pair<LL,LL>
#define INF 1e18
#define eps 1e-6
#define DB double
#define N 200010
LL n,m;
LL d[N],c[N][3],OP[N];
char a[N];
LL lowbit(LL x)
{
    return x & -x;
}
void add(LL l,LL w,LL ty)
{
    for(int i=l;i<=n;i+=lowbit(i))c[i][ty]+=w;
}
LL sum(LL l,LL ty)
{
    LL ans=0;
    for(int i=l;i;i-=lowbit(i))ans+=c[i][ty];
    return ans;
}
void check(LL x)
{
    if(x<1 || x>n)return ;
    LL cnt=0;
    add(x,-OP[x],1);
    OP[x]=0;
    if(x+1<=n)
    {
        if(sum(x,2)%26==sum(x+1,2)%26)cnt++;

    }
    if(x+2<=n)
    {
        if(sum(x,2)%26==sum(x+2,2)%26)cnt++;
    }
    add(x,cnt,1);
    OP[x]=cnt;
}
void solve()
{
    cin>>n>>m>>a+1;
    for(int i=1;i<=n;i++)
    {
        c[i][1]=c[i][2]=OP[i]=0;
    }
    LL ssum=0;
    for(int i=1;i<=n;i++)
    {
        LL tem=a[i]-'a';
        tem-=ssum;
        add(i,tem,2);
        ssum+=tem;
    }
    
    for(int i=1;i<=n;i++)check(i);
    for(int i=1;i<=m;i++)
    {
        LL op,l,r,x;
        cin>>op>>l>>r;
        if(op==1)cin>>x;
        if(op==1)
        {
            add(l,x,2);
            add(r+1,-x,2);
            check(l-2);check(l-1);
            check(r-1);check(r);
        }
        else 
        {
            LL ans=0;
            if(r-2>=l)ans+=sum(r-2,1)-sum(l-1,1);
            if(r-1>=l && sum(r-1,2)%26==sum(r,2)%26)ans++;
            if(ans==0)cout<<"YES"<<endl;
            else cout<<"NO"<<endl;
        }
    }

}
int main()
{
    //init();
   LL t=1;
   cin>>t;
   while(t--)solve();
        return 0;
}