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LazySegTree fix for custom join #6

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LazySegTree fix for custom join #6

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16 changes: 8 additions & 8 deletions Library/Data Structures/SegTreeLazy.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -5,26 +5,26 @@ template<typename T> struct SegTree {
vector<T> seg;
vector<T> lazy;
int N;
T NEUTRO = 0;
SegTree(int n) : N(n){ seg.assign(4*N, NEUTRO), lazy.assign(4*N, NEUTRO); }
T IDENTITY = T();
SegTree(int n) : N(n){ seg.assign(4*N, IDENTITY), lazy.assign(4*N, IDENTITY); }
SegTree(vector<T> &lista) : N(lista.size()){
seg.assign(4*N), lazy.assign(4*N, NEUTRO);
seg.assign(4*N, IDENTITY), lazy.assign(4*N, IDENTITY);
build(1, 0, N-1, lista);
}
T join(T lv, T rv){ return lv + rv; }
void unlazy(int no, int l, int r){
if(lazy[no] == NEUTRO) return;
if(lazy[no] == IDENTITY) return;
int m=(l+r)/2, e=no*2, d=e+1;

seg[no] += (r-l+1) * lazy[no]; /// Range Sum

if(l != r) lazy[e] += lazy[no], lazy[d] += lazy[no];
lazy[no] = NEUTRO;
lazy[no] = IDENTITY;
}

T query(int no, int l, int r, int a, int b){
unlazy(no, l, r);
if(b < l || r < a) return NEUTRO;
if(b < l || r < a) return IDENTITY;
if(a <= l && r <= b) return seg[no];
int m=(l+r)/2, e=no*2, d=e+1;

Expand Down Expand Up @@ -70,5 +70,5 @@ Build: O(N)
Query: O(log N) | seg.query(l, r);
Update: O(log N) | seg.update(l, r, v);
Unlazy: O(1)
**Update Join, NEUTRO, Update and Unlazy if needed**
*******************************************************/
**Update Join, IDENTITY, Update and Unlazy if needed**
*******************************************************/