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#include <fstream>
#include <algorithm>
using namespace std;
const int NMAX = 100005;
ifstream cin("aib.in");
ofstream cout("aib.out");
long long v[NMAX], aib[NMAX];
void update(int poz, long long val, int n)
{
for(int i = poz; i <= n; i += (i ^ (i - 1)) & i)
aib[i] += val;
}
long long query(int poz)
{
int sum = 0;
for(int i = poz; i > 0; i -= (i ^ (i - 1)) & i)
sum += aib[i];
return sum;
}
int bs1(long long a, int n)
{
int st = 1;
int dr = n;
int last = -1;
while(st <= dr) {
int med = (st + dr) / 2;
int q = query(med);
if(q <= a) {
if(q == a)
last = med;
st = med + 1;
}
else
dr = med - 1;
}
return last;
}
int bs2(long long a, int n)
{
long long ca = a;
int p = 1;
for(; p <= n; p = p << 1);
p = p >> 1;
int ans = 0;
for( ; p > 0; p = p >> 1) {
if(ans + p <= n && aib[ans + p] < a) {
ans += p;
a -= aib[ans];
}
}
ans++;
if(query(ans) == ca)
return ans;
else
return -1;
}
int main() {
int n, m;
cin >> n >> m;
for(int i = 1; i <= n; ++i) {
cin >> v[i];
update(i, v[i], n);
}
for(int i = 1; i <= m; ++i) {
int task;
cin >> task;
if(task == 0) {
int poz;
long long val;
cin >> poz >> val;
update(poz, val, n);
continue;
}
if(task == 1) {
int st, dr;
cin >> st >> dr;
cout << query(dr) - query(st - 1) << "\n";
continue;
}
// task = 2
long long a;
cin >> a;
// cout << bs1(a, n) << "\n";
cout << bs2(a, n) << "\n";
}
return 0;
}