STL-related

STL/STL-Set/set.cpp

@@ -0,0 +1,45 @@
+#include <iostream>
+#include <string>
+#include <set>
+using namespace std;
+int main(){
+	auto cmp = [](auto a, auto b){
+		return a > b;
+	};
+	set<int> a;
+	set<int> b = {1, 5, 4, 3, 3, 2};
+	set<int, decltype(cmp)> c(cmp);
+	a.insert(1);a.insert(5);a.insert(3);a.insert(2);
+	c.insert(1);c.insert(5);c.insert(3);c.insert(2);
+	a.emplace(6);
+	for(auto x : a){
+		cout << x << " ";
+	}
+	cout << endl;
+	for(auto x : c){
+		cout << x << " ";
+	}
+	cout << endl;
+	cout << a.count(3) << endl;
+	a.erase(6);
+	for(auto it = a.begin(); it != a.end(); it++){
+		cout << *it << " ";
+	}
+	//From "Smaller" To	"Bigger", To compare big, we need "func:cmp"
+	cout << endl;
+	cout << *(c.find(5))<< endl;
+	//lower_bound : >= val ; upper_bound : > val ;
+	cout << *(c.lower_bound(2)) << " " << *(c.upper_bound(2)) << endl;
+	cout << *(a.lower_bound(2)) << " " <<*(a.upper_bound(2)) << endl;
+	return 0;
+}
+/*
+COUT
+1 2 3 5 6
+5 3 2 1
+1
+1 2 3 5
+5
+2 1
+2 3
+*/