fix persistent and add test

2 files changed, 11 insertions, 1 deletions

diff --git a/datastructures/persistent.cpp b/datastructures/persistent.cpp
index 0a65a79..4093cdc 100644
--- a/datastructures/persistent.cpp
+++ b/datastructures/persistent.cpp
@@ -7,7 +7,7 @@ struct persistent {
 		: time(time), data(1, {time, value}) {}

 	

 	T get(int t) {

-		return prev(upper_bound(all(data), {t+1, {}}))->second;

+		return prev(upper_bound(all(data), pair{t+1, T{}}))->second;

 	}

 	

 	int set(T value) {

diff --git a/datastructures/test/persistent.cpp b/datastructures/test/persistent.cpp
new file mode 100644
index 0000000..d98569b
--- /dev/null
+++ b/datastructures/test/persistent.cpp
@@ -0,0 +1,10 @@
+#include "../persistent.cpp"
+
+int main() {
+	int time = 0;
+	persistent<int> p(time, 0);
+	p.set(1);
+	int t1 = time;
+	p.set(2);
+	assert(p.get(t1) == 1);
+}