#include <stdio.h>
#include <stdlib.h>
#define zeros(x) ((x^(x-1))&x)
#define MAXN 100001
int aib[MAXN],n;
inline void add(int x,int nr){
    int i;
    for(i=x;i<=n;i=i+zeros(i))
        aib[i]+=nr;
}
inline int sum(int x){
    int i,s=0;
    for(i=x;i>0;i=i-zeros(i))
        s=s+aib[i];
    return s;
}
int main(){
    FILE*fi,*fout;
    int i,j,st,m,dr,mij,t,a,b,nr;
    fi=fopen("aib.in" ,"r");
    fout=fopen("aib.out" ,"w");
    fscanf(fi,"%d%d" ,&n,&m);
    for(i=1;i<=n;i++){
        fscanf(fi,"%d" ,&nr);
        add(i,nr);
    }
    for(i=0;i<m;i++){
        fscanf(fi,"%d" ,&t);
        if(t==0){
            fscanf(fi,"%d%d" ,&a,&b);
            add(a,b);
        }
        if(t==1){
            fscanf(fi,"%d%d" ,&a,&b);
            fprintf(fout,"%d\n" ,sum(b)-sum(a-1));
        }
        if(t==2){
            fscanf(fi,"%d" ,&a);
            st=1;
            dr=n+1;
            while(dr-st>1){
                mij=(st+dr)/2;
                if(sum(mij)>a)
                   dr=mij;
                else
                    st=mij;
            }
            fprintf(fout,"%d\n" ,st);
        }
    }
    fclose(fi);
    fclose(fout);
    return 0;
}