HackerEarth: Shil and Palindrome Research ( BIT on XOR )

HackerEarth: Shil and Palindrome Research ( BIT on XOR )
///==================================================///
///                HELLO WORLD !!                    ///
///                  IT'S ME                         ///
///               BISHAL GAUTAM                      ///
///         [ bsal.gautam16@gmail.com ]              ///
///==================================================///
#include<bits/stdc++.h>
#define X first
#define Y second
#define mpp make_pair
#define nl printf("\n")
#define SZ(x) (int)(x.size())
#define pb(x) push_back(x)
#define pii pair<int,int>
#define pll pair<ll,ll>
///---------------------
#define S(a) scanf("%d",&a)
#define P(a) printf("%d",a)
#define SL(a) scanf("%lld",&a)
#define S2(a,b) scanf("%d%d",&a,&b)
#define SL2(a,b) scanf("%lld%lld",&a,&b)
///------------------------------------
#define all(v) v.begin(),v.end()
#define CLR(a) memset(a,0,sizeof(a))
#define SET(a) memset(a,-1,sizeof(a))
#define fr(i,a,n) for(int i=a;i<=n;i++)
using namespace std;
typedef long long ll;
///==========CONSTANTS=============///
///  Digit     0123456789012345678 ///
#define MX     100002
#define inf    1000000010
#define MD     1000000007LL
#define eps    1e-9
///===============================///

int n;
char s[MX+2];
/*
int BIT[27][MX+5];
void add(int id,int p,int v) {
    for(int i=p; i<=MX; i+=i&-i)BIT[id][i]+=v;
}
int read(int id,int p) {
    int ret=0;
    for(int i=p; i>0; i-=i&-i)ret+=BIT[id][i];
    return ret;
}
*/
int bit[MX+5];
void add(int p,int v) {
    for(int i=p; i<=MX; i+=i&-i)bit[i]^=v;
}
int read(int p) {
    int ret=0;
    for(int i=p; i>0; i-=i&-i)ret^=bit[i];
    return ret;
}
int main() {
    int q,x,y,i;
    S2(n,q);
    scanf("%s",s);
    for(i=1; i<=n; i++) {
        int id=s[i-1]-'a';
        //add( id,i,+1 );
        add(i,(1<<id));
    }
    while(q--) {
        int op;
        S(op);
        if(op==1) {
            S(x);
            char ch;
            scanf(" %ch",&ch);
            int id=ch-'a';
            int pid=s[ x-1 ]-'a';
            s[ x-1 ]=ch;

//            add( pid, x ,-1 );
//            add( id, x ,+1 );

            int nval=((1<<pid)^(1<<id));
            add( x,nval );
        } else {
            S2(x,y);

//            int od=0;
//            for(int i=0; i<26; i++) {
//                int sm=read(i,y)-read(i,x-1);
//                if(sm&1)od++;
//                if(od>=2)break;
//            }
//            if(od<=1) printf("yes\n");
//            else printf("no\n");

            int bt=read(y)^read(x-1);
            int bc=__builtin_popcount(bt);
            if(bc<=1) printf("yes\n");
            else printf("no\n");
        }
    }
    return 0;
}