#include <cstdio>
#define MAX 100010
int n,sum[MAX];

void update(int idx,int val){
    while(idx<=n){
        sum[idx]+=val;
        idx+=idx&-idx;
    }
}

int read(int idx){
    int s=0;
    while(idx>0){
        s+=sum[idx];
        idx-=idx&-idx;
    }
    return s;
}

int cbinar(int x){
    int l=1,r=n,md;
    while(l<r){
        md=(l+r)/2;
        if(read(md)>=x)r=md; else l=md+1;
    }
    return read(l)==x?l:-1;
}

int main(){
    int c,m,x,y;
    freopen("aib.in","r",stdin);
    freopen("aib.out","w",stdout);
        scanf("%d %d",&n,&m);
        for(int i=1;i<=n;i++)
        {
            scanf("%d",&x);
            update(i,x);
        }
        for(int i=1;i<=m;i++)
        {
            scanf("%d",&c);
            switch(c){
                case 0: scanf("%d %d",&x,&y);
                    update(x,y); break;
                case 1: scanf("%d %d",&x,&y);
                    printf("%d\n",read(y)-read(x-1)); break;
                case 2: scanf("%d",&x);
                    printf("%d\n",cbinar(x)); break;
            }
        }
}