Next permutation

Author: ivorynoise

palindrome-d.cpp

@@ -0,0 +1,24 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int main() {
+	string s;
+	cin >> s;
+
+	int l = s.size() / 2;
+	sort(s.begin(), s.begin() + l);
+	// cout << s << endl;
+
+	do {
+
+		copy(s.begin(), s.begin() + l, ostream_iterator<char>(cout, ""));
+		if (s.size() & 1) cout << s[l];
+		// copy(s.rbegin()-l, s.rend(), ostream_iterator<char>(cout, ""));
+		//doesn't work
+
+		for(int i = l - 1; i >=0; --i) cout << s[i];
+
+		cout << "\n";
+
+	} while (next_permutation(s.begin(), s.begin() + l));
+}

palindrome-h.cpp

@@ -0,0 +1,34 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+int main() {
+    char s[100010],half[100010];
+    cin>>s;
+    int i,len=strlen(s);
+    for(i=0;i<len/2;i++){
+        half[i]=s[i];
+    }
+    sort(half,half+len/2);
+    if(len%2==0){
+        do{
+            cout<<half;
+            for(int i=len/2-1;i>=0;i--){
+                cout<<half[i];
+            }
+            cout<<"\n";
+        }while(next_permutation(half,half+len/2));
+        
+    }
+    else{
+        do{
+            cout<<half;
+            cout<<s[len/2];
+            for(int i=len/2-1;i>=0;i--){
+                cout<<half[i];
+            }
+            cout<<"\n";
+        }while(next_permutation(half,half+len/2));
+        
+    }
+	return 0;
+}