ADDED GRAPH ALGORITHM

Graph Algorithms/Strongly Connected Component.cpp

@@ -0,0 +1,54 @@
+//(Detection of Directed Cycle in a connected component): http://codeforces.com/contest/505/problem/D
+vector<int> g[N], newg[N], rg[N], todo;
+int comp[N], indeg[N]; 
+bool vis[N];
+vector<int> gr[N];
+
+void dfs(int k)
+{
+    vis[k]=1;
+    for(auto it:g[k])
+    {
+        if(!vis[it])
+            dfs(it);
+    }
+    todo.push_back(k);
+}
+
+void dfs2(int k, int val)
+{
+    comp[k]=val;
+    for(auto it:rg[k])
+    {
+        if(comp[it]==-1)
+            dfs2(it, val);
+    }
+}
+
+void sccAddEdge(int from, int to)
+{
+    g[from].push_back(to);
+    rg[to].push_back(from);
+}
+
+void scc()
+{
+    for(int i=1;i<=n;i++)
+        comp[i]=-1;
+
+    for(int i=1;i<=n;i++)
+    {
+        if(!vis[i])
+            dfs(i);
+    }
+
+    reverse(todo.begin(), todo.end());
+
+    for(auto it:todo)
+    {
+        if(comp[it]==-1)
+        {
+            dfs2(it, ++grp);
+        }
+    }
+}

Recursion, Backtracking etc/K-Combinations.cpp

@@ -0,0 +1,54 @@
+/*
+ Petar 'PetarV' Velickovic
+ Algorithm: K-Combinations
+*/
+
+#include <stdio.h>
+#include <math.h>
+#include <string.h>
+#include <iostream>
+#include <vector>
+#include <list>
+#include <string>
+#include <algorithm>
+#include <queue>
+#include <stack>
+#include <set>
+#include <map>
+#include <complex>
+using namespace std;
+typedef long long lld;
+
+int n, k;
+int skup[100];
+bool inSet[100];
+
+//Program koji generise sve kombinacije od po K elemenata datog skupa
+//Slozenost: O((n choose k))
+
+void kCombinations(int pos, int amt)
+{
+    if (n-pos<k-amt) return;
+    if (amt==k)
+    {
+        for (int i=0;i<n;i++) if (inSet[i]) printf("%d ",skup[i]);
+        printf("\n");
+        return;
+    }
+    inSet[pos] = true;
+    kCombinations(pos+1,amt+1);
+    inSet[pos] = false;
+    kCombinations(pos+1,amt);
+}
+
+int main()
+{
+    n = 5, k = 2;
+    skup[0] = 1;
+    skup[1] = 2;
+    skup[2] = 3;
+    skup[3] = 4;
+    skup[4] = 5;
+    kCombinations(0, 0);
+    return 0;
+}

Recursion, Backtracking etc/Permutations.cpp

@@ -0,0 +1,57 @@
+/*
+ Petar 'PetarV' Velickovic
+ Algorithm: Permutations
+*/
+
+#include <stdio.h>
+#include <math.h>
+#include <string.h>
+#include <iostream>
+#include <vector>
+#include <list>
+#include <string>
+#include <algorithm>
+#include <queue>
+#include <stack>
+#include <set>
+#include <map>
+#include <complex>
+using namespace std;
+typedef long long lld;
+
+int n;
+int niz[100];
+bool inPerm[100];
+int currPerm[100];
+
+//Algoritam koji generise sve permutacije datog niza
+//Slozenost: O(n!)
+
+void generatePermutations(int pos)
+{ 
+    if (pos == n)
+    {
+        for (int i=0;i<n;i++) printf("%d ",currPerm[i]);
+        printf("\n");
+    }
+    for (int i=0;i<n;i++)
+    {
+        if (!inPerm[i])
+        {
+            currPerm[pos] = niz[i];
+            inPerm[i] = true;
+            generatePermutations(pos+1);
+            inPerm[i] = false;
+        }
+    }
+}
+
+int main()
+{
+    n = 3;
+    niz[0] = 1;
+    niz[1] = 2;
+    niz[2] = 3;
+    generatePermutations(0);
+    return 0;
+}

Recursion, Backtracking etc/Power Set.cpp

@@ -0,0 +1,51 @@
+/*
+ Petar 'PetarV' Velickovic
+ Algorithm: Power Set
+*/
+
+#include <stdio.h>
+#include <math.h>
+#include <string.h>
+#include <iostream>
+#include <vector>
+#include <list>
+#include <string>
+#include <algorithm>
+#include <queue>
+#include <stack>
+#include <set>
+#include <map>
+#include <complex>
+using namespace std;
+typedef long long lld;
+
+//Metoda koja generise partitivni skup nekog skupa
+//Slozenost: O(2^n)
+
+int n;
+int skup[100];
+bool inSet[100];
+
+void powerSet(int pos)
+{
+    if (pos==n)
+    {
+        for (int i=0;i<n;i++) if (inSet[i]) printf("%d ",skup[i]);
+        printf("\n");
+        return;
+    }
+    inSet[pos] = false;
+    powerSet(pos+1);
+    inSet[pos] = true;
+    powerSet(pos+1);
+}
+
+int main()
+{
+    n = 3;
+    skup[0] = 1;
+    skup[1] = 2;
+    skup[2] = 3;
+    powerSet(0);
+    return 0;
+}