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#include <iostream>
#include <fstream>
#include <cstring>
#include <stack>
using namespace std;
ifstream in("aib.in");
ofstream out("aib.out");
typedef long long ll;
const int NMax = 1e5 + 5;
int N,M;
int aib[NMax];
void update(int,int);
int query(int);
int querySingle(int);
int findK(int);
int main() {
in>>N>>M;
for (int i=1;i <= N;++i) {
int val;
in>>val;
update(i,val);
}
while (M--) {
int tip,a,b;
in>>tip;
if (!tip) {
in>>a>>b;
update(a,b);
}
else if (tip == 1) {
in>>a>>b;
if (a == b) {
out<<querySingle(a)<<'\n';
}
else {
out<<query(b) - query(a-1)<<'\n';
}
}
else {
in>>a;
//out<<"PlaceHolder"<<'\n';
out<<findK(a)<<'\n';
}
}
in.close();out.close();
return 0;
}
void update(int pos,int val) {
while (pos <= N) {
aib[pos] += val;
pos += pos & (~pos + 1);
}
}
int query(int pos) {
int sum = 0;
while (pos) {
sum += aib[pos];
pos -= pos & (~pos + 1);
}
return sum;
}
int querySingle(int pos) {
int sum1 = aib[pos],
sum2 = 0,
pre = pos - 1,
lca = pos - (pos & (~pos + 1));
while (pre != lca) {
sum2 += aib[pre];
pre -= pre & (~pre + 1);
}
return sum1 - sum2;
}
int findK(int sum) {
int pw;
for (pw = 1;pw <= N; pw <<= 1) ;
pw >>= 1;
int pos = 0;
while (pw) {
if (pos + pw <= N && aib[pos + pw] <= sum) {
sum -= aib[pos += pw];
}
pw >>= 1;
}
if (!sum) {
return pos;
}
return -1;
}