Pagini recente » Cod sursa (job #433862) | Cod sursa (job #2186260) | Cod sursa (job #101956) | Cod sursa (job #829500) | Cod sursa (job #2696760)
#include <bits/stdc++.h>
#define ll long long
#define cin fin
#define cout fout
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int n, m, a, b, val;
int bit[400099];
void update(int index, int add) {
for (; index <= n; index += index & (-index))
bit[index] += add;
}
int prefixSum(int index) {
int result = 0;
for (; index; index -= index & (-index))
result += bit[index];
return result;
}
int sumOfInterval(int a, int b) {
return prefixSum(b) - prefixSum(a - 1);
}
int main() {
ios :: sync_with_stdio(0);
cin.tie(0);
cin >> n >> m;
for (int i = 1; i <= n; i++) {
cin >> val;
update(i, val);
}
int type;
for (int query = 1; query <= m; query++) {
cin >> type;
if (!type) {
cin >> a >> b;
update(a, b);
} else if (type == 1) {
cin >> a >> b;
cout << sumOfInterval(a, b) << '\n';
} else {
cin >> val;
//binary searching for the answer
int i, add;
for (add = 1; add < n; add <<= 1);
for (i = 0; add; add >>= 1)
if (i + add <= n && prefixSum(i + add) <= val)
i += add;
if (prefixSum(i) == val)
cout << i << '\n';
else
cout << "-1\n";
}
}
return 0;
}