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--- cpp:stl:vector [2020/05/27 16:54] – [Διαγραφή των περιεχομένων του πίνακα] gthanos
+++ cpp:stl:vector [2020/05/27 16:56] – gthanos
@@ Line 133: / Line 133: @@
     ints.erase(ints.begin());    // erase the first element.
     ints.erase(ints.end()-1);    // erase the laste element.
+    print(ints);
+  }
+}
+</code>
+<code cpp vector_erase_03.cpp>
+#include <vector>
+#include <list>
+#include <iostream>
+#include <iomanip>
+using namespace std;
+template<typename T>
+void print(vector<T> v) {
+  for(auto it = v.cbegin(); it!=v.cend(); it++)
+    cout << setw(3) << *it;
+  cout << endl;
+}
+template<typename T>
+void print_r(vector<T> v) {
+  for(auto it = v.crbegin(); it!=v.crend(); it++)
+    cout << setw(3) << *it;
+  cout << endl;
+}
+int main() {
+  vector<int> ints;                  // initially zero size
+  for(int i=0; i<10; i++) {
+    ints.push_back(i+1);             // insert to the end - very fast
+    ints.insert(ints.begin(),i+1);   // insert to the beginning - extremely slow
+  }
+  print(ints);
+  while(ints.size() > 0) {
+    ints.erase(ints.begin(), ints.end());    // erase everything!
     print(ints);
   }