#include <cstdio>

#define lsb(x) (x & (-x))
FILE *fin = freopen("aib.in","r",stdin); FILE *fout = freopen("aib.out","w",stdout);

const int nmax = 100000 + 5;

/* -------- Data --------*/
int n, m;
int aib[nmax];
/* -------- Data --------*/

void Update(int position, int value)
{
    for(int i = position; i <= n; i+= lsb(i))
    {
        aib[i] += value;
    }
}

int Query(int position)
{
    int result = 0;
    for(int i =position; i> 0 ; i-=lsb(i))
    {
        result+=aib[i];
    }
    return result;
}

void ReadInput()
{
    int x, op, a,b;
    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",&op);
        if(op==0)
        {
            scanf("%d%d",&a,&b);
            Update(a,b);
        }
        else if(op==1)
        {
            scanf("%d%d",&a,&b);
            printf("%d\n",Query(b) - Query(a-1));
        }
        else
        {
            int pas=1,k=0;
            scanf("%d",&a);
            for(;pas<=n;pas<<=1);
            for(; pas ; pas >>= 1)
            {
                if(k+pas <= n && Query(k+pas)<=a)
                    k+=pas;
            }
            if(Query(k)==a)
                printf("%d\n",k);
            else
                printf("-1\n");
        }
    }
}

int main()
{
    ReadInput();
}