diff options
Diffstat (limited to 'datastructures/fenwickTree2.cpp')
| -rw-r--r-- | datastructures/fenwickTree2.cpp | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/datastructures/fenwickTree2.cpp b/datastructures/fenwickTree2.cpp index ff87e2e..7fcdbb9 100644 --- a/datastructures/fenwickTree2.cpp +++ b/datastructures/fenwickTree2.cpp @@ -1,21 +1,21 @@ vector<ll> add, mul; void update(int l, int r, ll val) { - for (int tl = l + 1; tl < sz(add); tl += tl&(-tl)) + for (int tl = l + 1; tl < ssize(add); tl += tl & -tl) add[tl] += val, mul[tl] -= val * l; - for (int tr = r + 1; tr < sz(add); tr += tr&(-tr)) + for (int tr = r + 1; tr < ssize(add); tr += tr & -tr) add[tr] -= val, mul[tr] += val * r; } -void init(vector<ll>& v) { - mul.assign(sz(v) + 1,0); - add.assign(sz(v) + 1,0); - for(int i = 0; i < sz(v); i++) update(i, i + 1, v[i]); +void init(vector<ll> &v) { + mul.assign(size(v) + 1, 0); + add.assign(size(v) + 1, 0); + for(int i = 0; i < ssize(v); i++) update(i, i + 1, v[i]); } -ll prefix_sum (int i) { - ll res = 0; i++; - for (int ti = i; ti > 0; ti -= ti&(-ti)) +ll prefix_sum(int i) { + ll res = 0; + for (int ti = i; ti > 0; ti &= ti-1) res += add[ti] * i + mul[ti]; return res; } |