Pagini recente » Cod sursa (job #2589010) | Cod sursa (job #1983130) | Cod sursa (job #1826236) | Cod sursa (job #1149629) | Cod sursa (job #3152832)
#include <bits/stdc++.h>
using namespace std;
int n, m;
vector <int> BIT(100001, 0);
void update(int i, int val)
{
while(i<=n)
{
BIT[i]+=val;
i+=(i&-i);
}
}
int presum(int i)
{
int sum=0;
while(i>0)
{
sum+=BIT[i];
i-=(i&-i);
}
return sum;
}
int main()
{
ifstream cin("aib.in");
ofstream cout("aib.out");
int a, b, c;
cin >> n >> m;
for(int i=1; i<=n; i++)
{
cin >> a;
update(i, a);
}
for(int i=1; i<=m; i++)
{
cin >> c;
//cout << "i=" << i << " c=" << c << " ";
if(c==0)
{
cin >> a >> b;
update(a, b);
}
else if(c==1)
{
cin >> a >> b;
//cout << a << " " << b << " " << presum(b) << " " << presum(a-1) << " ";
cout << presum(b)-presum(a-1) << "\n";
}
else if(c==2)
{
//cout << "OK ";
cin >> a;
//cout << a << " ";
int l=1, r=n, mid;
while(l<r)
{
mid=(l+r+1)/2;
if(presum(mid)<=a)
l=mid;
else r=mid-1;
}
if(presum(l)==a)
cout << l << "\n";
else cout << "-1\n";
}
//cout << "\n";
}
return 0;
}