Update segment_tree_v3.cpp

1 files changed, 11 insertions, 2 deletions

diff --git a/Data Structures/segment_tree_v3.cpp b/Data Structures/segment_tree_v3.cpp
index 2d29ff2..6308b9a 100644
--- a/Data Structures/segment_tree_v3.cpp
+++ b/Data Structures/segment_tree_v3.cpp
@@ -5,9 +5,18 @@ inline void push(int l, int r, int n) {
 	if (l != r) tmp[n << 1] += tmp[n], tmp[n << 1 | 1] += tmp[n];
 	tmp[n] = 0;
 }
+void update(int x, T v, int l = 0, int r = -1, int n = 1) {
+	if (r == -1) r = N - 1;
+	if (l == r) seg[n] += v;
+	else {
+		int m = (l + r) >> 1;
+		x <= m ? update(x, v, l, m, n << 1) : update(x, v, m + 1, r, n << 1 | 1);
+		seg[n] = pull(seg[n << 1], seg[n << 1 | 1]);
+	}
+}
 void update(int a, int b, int v, int l = 0, int r = -1, int n = 1) {
 	if (r == -1) r = N - 1;
-	if (tmp[n]) push(l, r, n);
+	push(l, r, n);
 	if (l > b || r < a) return;
 	if (l >= a && r <= b) {
 		tmp[n] += v;
@@ -22,7 +31,7 @@ void update(int a, int b, int v, int l = 0, int r = -1, int n = 1) {
 int query(int a, int b, int l = 0, int r = -1, int n = 1) {
 	if (r == -1) r = N - 1;
 	if (a > b || l > b || r < a) return 0;
-	if (tmp[n]) push(l, r, n);
+	push(l, r, n);
 	if (l >= a && r <= b) return seg[n];
 	int m = (l + r) >> 1;
 	return pull(query(a, b, l, m, n << 1), query(a, b, m + 1, r, n << 1 | 1));