From 5ab8a5088b729a9953b8dff1b2a985dc8fb2098b Mon Sep 17 00:00:00 2001 From: mzuenni Date: Mon, 27 Jun 2022 17:19:28 +0200 Subject: updated tcr --- datastructures/RMQ.cpp | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 datastructures/RMQ.cpp (limited to 'datastructures/RMQ.cpp') diff --git a/datastructures/RMQ.cpp b/datastructures/RMQ.cpp new file mode 100644 index 0000000..b38b838 --- /dev/null +++ b/datastructures/RMQ.cpp @@ -0,0 +1,27 @@ +vector values; +vector> rmq; + +int select(int a, int b) { + return values[a] <= values[b] ? a : b; +} + +void build() { + for(int i = 0, s = 1, ss = 1; s <= values.size(); ss=s, s*=2, i++) { + for(int l = 0; l + s <= values.size(); l++) { + if(i == 0) rmq[0][l] = l; + else { + int r = l + ss; + rmq[i][l] = select(rmq[i-1][l], rmq[i-1][r]]); +}}}} + +void init(vector& v) { + values = v; + rmq = vector>(floor(log2(values.size()))+1, vector(values.size())); + build(); +} + +int query(int l, int r) { + if(l >= r) return l; + int s = floor(log2(r-l)); r = r - (1 << s); + return select(rmq[s][l],rmq[s][r]); +} \ No newline at end of file -- cgit v1.2.3