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#include <cstdio>
#define putere(x) (x)&(-x)
using namespace std;
int aib[100010],n,m,i,x,y,p,a,maxlog;
void aib_update(int i,int s)
{
for(;i<=n;i+=putere(i)) aib[i]+=s;
}
int aib_query(int i)
{
int s=0;
for(;i>0;i-=putere(i)) s+=aib[i];
return s;
}
int main()
{
freopen("aib.in", "r", stdin);
freopen("aib.out", "w", stdout);
scanf("%d%d",&n,&m);
for(i=1;i<=n;i++)
{
scanf("%d",&x);
aib_update(i,x);
}
for(maxlog=1;maxlog<=n;maxlog<<=1);
maxlog>>=1;
for(;m;m--)
{
scanf("%d%d",&p,&x);
if(p==0)
{
scanf("%d",&y);
aib_update(x,y);
}
else if(p==1)
{
scanf("%d",&y);
printf("%d\n",aib_query(y)-aib_query(x-1));
}
else
{
a=0;
for(i=maxlog;i;i>>=1)
{
if(a+i>n) continue;
if(aib[a+i]<=x)
{
a+=i;
x-=aib[a];
}
}
if(x==0) printf("%d\n",a);
else printf("-1\n");
}
}
return 0;
}