Hashing implementation with chaining collision resolution

Author: vasutomar

Hashing/Chaining.cpp

@@ -0,0 +1,132 @@
+#include<iostream>
+#include<math.h>
+using namespace std;
+struct node{
+	int data;
+	struct node *next;
+} *head[100],*curr;
+
+void init(){
+	for(int i=0;i<100;i++)
+		head[i]=NULL;
+}
+
+void add(int x,int h){
+	struct node *temp = new node;
+	temp->data = x;
+	temp->next = NULL;
+	if(head[h]==NULL){
+		head[h] = temp;
+		curr=head[h];
+	}
+	else{
+		curr=head[h];
+		while(curr->next!=NULL)
+			curr=curr->next;
+		curr->next = temp;
+	}
+}
+
+void display(int mod){
+	struct node *temp;
+	int i;
+	for(i=0;i<mod;i++){
+		if(head[i]==NULL){
+			cout<<"Key = "<<i<<" is empty"<<endl;
+		}
+		else{
+			cout<<"Key = "<<i<<" Value = ";
+			temp = head[i];
+			while(temp->next!=NULL){
+				cout<<temp->data<<" ";
+				temp=temp->next;
+			}
+			cout<<temp->data;
+			cout<<endl;
+		}
+	}
+}
+
+int hash(int x,int mod){
+	return x%mod;
+}
+
+void find(int x,int h){
+	struct node *temp =head[h];
+	if(head[h]==NULL){
+		cout<<"Element not found";
+		return;
+	}
+	while(1){
+		if(temp->data==x)
+			break;
+		else if(temp->next==NULL)
+			break;
+		temp=temp->next;
+	}
+	if(temp->next!=NULL)
+		cout<<"Element found";
+	else{
+		if(temp->data==x)
+			cout<<"Element found";
+		else
+			cout<<"Element not found";
+	}
+}	
+
+int main(void){
+	init();
+	int c,x,mod;
+	cout<<"Enter the size of Hash Table. = ";
+	cin>>mod;
+	while(1){
+		cout<<endl;
+		cout<<"PLEASE CHOOSE -"<<endl;
+		cout<<"1. Add element."<<endl;
+		cout<<"2. Find element."<<endl;
+		cout<<"3. Generate Hash."<<endl;
+		cout<<"4. Display Hash table."<<endl;
+		cout<<"5. Exit."<<endl;
+		cin>>c;
+		switch(c){
+			case 1:{
+				cout<<"Enter element to add = ";
+				cin>>x;
+				int h = hash(x,mod);
+				if(h<0)
+					h=fabs(h);
+				add(x,h);
+				break;
+			}
+			case 2:{
+				cout<<"Enter element to search = ";
+				cin>>x;
+				int h=hash(x,mod);
+				find(x,h);
+				break;
+			}
+			case 3:{
+				cout<<"Enter element to generate hash = ";
+				cin>>x;
+				cout<<"Hash of "<<x<<" is = "<<hash(x,mod);
+				break;
+			}
+			case 4:{
+				display(mod);
+			}
+			default:{
+				break;
+			}
+		}
+		if(c>4)
+			break;
+		cout<<endl;
+	}
+	/*add(1,&head1);
+	add(2,&head1);
+	add(3,&head2);
+	add(5,&head1);
+	display(&head1);
+	display(&head2);*/
+	return 0;
+}