From 40898696c7880d877b111749ed7076d904e4cc14 Mon Sep 17 00:00:00 2001
From: MishaalAslam <109417825+MishaalAslam@users.noreply.github.com>
Date: Mon, 24 Oct 2022 16:44:24 +0500
Subject: [PATCH] Added a twin prime number code

I have added a Twin prime number find code in C
---
 Algorithms/C++/dfs.cpp   | 63 +++++++++++++++++++++++++---------------
 Algorithms/C/twinPrime.c | 46 +++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+), 23 deletions(-)
 create mode 100644 Algorithms/C/twinPrime.c

diff --git a/Algorithms/C++/dfs.cpp b/Algorithms/C++/dfs.cpp
index ca0c3039..4dfef951 100644
--- a/Algorithms/C++/dfs.cpp
+++ b/Algorithms/C++/dfs.cpp
@@ -1,24 +1,41 @@
-class Graph 
+#include<iostream>
+#include<stdio.h>
+#include<stdlib.h>
+using namespace std;
+int cost[10][10],i,j,k,n,stk[10],top,v,visit[10],visited[10];
+int main()
 {
-public:
-    map<int, bool> visited;
-    map<int, list<int>> adj;
-    void addEdge(int v, int w);
-    void DFS(int v);
-};
-  
-void Graph::addEdge(int v, int w)
-{
-    adj[v].push_back(w);
-}
-  
-void Graph::DFS(int v)
-{
-    visited[v] = true;
-    cout << v << " ";
-    list<int>::iterator i;
-    for (i = adj[v].begin(); i != adj[v].end(); ++i)
-        if (!visited[*i])
-            DFS(*i);
-}
-  
\ No newline at end of file
+    int m;
+    cout <<"Enter no of vertices: ";
+    cin >> n;
+    cout <<"Enter no of edges: ";
+    cin >> m;
+    cout <<"\nEDGES \n";
+    for(k=1; k<=m; k++)
+    {
+        cin >>i>>j;
+        cost[i][j]=1;
+    }
+    cout <<"Enter initial vertex to traverse from: ";
+    cin >>v;
+    cout <<"DFS ORDER OF VISITED VERTICES: ";
+    cout << v <<" ";
+    visited[v]=1;
+    k=1;
+    while(k<n)
+    {
+        for(j=n; j>=1; j--)
+            if(cost[v][j]!=0 && visited[j]!=1 && visit[j]!=1)
+            {
+                visit[j]=1;
+                stk[top]=j;
+                top++;
+            }
+        v=stk[--top];
+        cout<<v << " ";
+        k++;
+        visit[v]=0;
+        visited[v]=1;
+    }
+    return 0;
+}
\ No newline at end of file
diff --git a/Algorithms/C/twinPrime.c b/Algorithms/C/twinPrime.c
new file mode 100644
index 00000000..c7d82f71
--- /dev/null
+++ b/Algorithms/C/twinPrime.c
@@ -0,0 +1,46 @@
+//twin Primes
+#define _CRT_SECURE_NO_WARNINGS
+
+#include<stdio.h>
+int main()
+{
+	
+	int num;
+	int prime;
+	printf("Enter a positive Integer: ");
+	scanf("%d", &num); //taking input
+
+	while (num < 0)
+	{
+		printf("Invalid input!\nEnter Positive Integer Again: ");
+		scanf("%d", &num);
+	}
+
+	for (int i = 3; i < num; i++)
+	{
+		prime = 0;
+		for (int j = 3; j < i; j++)
+		{
+			if (i % j == 0 || (i + 2) % j == 0)
+			{
+				prime = 1;
+			}
+		}
+		
+		if (prime == 0)
+		{
+			//printf("Twin prime numbers between 2 and %d are ", num);
+			printf("(%d,%d)", i, i + 2);
+			printf("\n");
+		}
+	}
+
+
+
+
+
+
+
+
+	return 0;
+}
\ No newline at end of file