advance_next_prev.cpp

Author: keineahnung2345

advance_next_prev.cpp

@@ -0,0 +1,29 @@
+#include <iostream>
+#include <map>
+
+using namespace std;
+
+int main()
+{
+    map<int, char> mymap = {{1,'a'}, {2,'b'}, {3,'c'}, 
+    {4,'d'}, {5,'e'}, {6,'f'}, {7,'g'}, {8,'h'}, {9, 'i'}, {10, 'j'}};
+    
+    auto it = mymap.begin();
+
+    //std::advance change its argument directly and return void
+    advance(it, 4);
+    cout << it->first << ", " << it->second << endl; //5, e
+
+    advance(it, -2);
+    cout << it->first << ", " << it->second << endl; //3, c
+    
+    //std::next doesn't change its argument but make a copy
+    auto it2 = next(it, 4);
+    cout << it2->first << ", " << it2->second << endl; //7, g
+    
+    //std::prev doesn't change its argument but make a copy
+    auto it3 = prev(it2, 3);
+    cout << it3->first << ", " << it3->second << endl; //4, d
+    
+    return 0;
+}