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#include <fstream>
#include <iostream>
using namespace std;
const char infile[] = "aib.in";
const char outfile[] = "aib.out";
ifstream fin(infile);
ofstream fout(outfile);
const int MAXN = 100005;
const int oo = 0x3f3f3f3f;
int N, M, aib[MAXN];
inline int lsb(int x) {
return x & (-x);
}
inline void Update(int pos, int value) {
for(int i = pos ; i <= N ; i += lsb(i))
aib[i] += value;
}
inline int Query(int pos) {
int sum = 0;
for(int i = pos ; i ; i -= lsb(i))
sum += aib[i];
return sum;
}
inline int binarySearch(int value) {
int li = 1, ls = N, ans = -1;
while(li <= ls) {
int mid = ((li + ls) >> 1);
int val = Query(mid);
if(val >= value) {
ls = mid - 1;
if(val == value)
ans = mid;
}
else li = mid + 1;
}
return ans;
}
int main() {
fin >> N >> M;
for(int i = 1; i <= N ; ++ i) {
int X;
fin >> X;
Update(i, X);
}
for(int i = 1 ; i <= M ; ++ i) {
int op, a, b;
fin >> op;
switch(op) {
case 0:
fin >> a >> b;
Update(a, b);
break;
case 1:
fin >> a >> b;
fout << Query(b) - Query(a - 1) << '\n';
break;
case 2:
fin >> a;
fout << binarySearch(a) << '\n';
break;
}
}
fout.close();
return 0;
}