Assignment_1

#include <iostream>
#include <string>
#include <vector>
#include <fstream>
#include <cstdlib>
#define MOD 101
#define SIZE 101
using namespace std;

class Symbolinfo
{
public:
    string identifier;
    string name;
    Symbolinfo(string identifier, string name)
    {
        this->identifier = identifier;
        this->name = name;
    }

};
class SymbolTable
{
public:
    vector<Symbolinfo> table[SIZE];
};
int hashFunction(string identifier)
{
    int r = 4 + 3;
    int len = identifier.length();
    if(len%2 == 0){
        char c1, c2;
        c1 = identifier[0];
        c2 = identifier[1];
        int sub = abs(c1 - c2);
        int ascii = 0;
        int j = 0;
        for(int i = 0; i < sub; i++, j += 2){
            ascii += identifier[j];
            if(j >= len){
                j = 0;
            }
        }
        ascii = ascii * 2 * 2 * 2 * 2 * 2 * 2 * 2;
        ascii = ascii % MOD;
        return ascii;

    }
    else {
        char c1, c2;
        c1 = identifier[len - 1];
        c2 = identifier[len - 2];
        int sub = abs(c1 - c2);
        int ascii = 0;
        int j = 1;
        for(int i = 0; i < sub; i++, j += 2){
            ascii += identifier[j];
            if(j >= len){
                j = 1;
            }
        }
        ascii = ascii * 2 * 2 * 2 * 2 * 2 * 2 * 2;
        ascii = ascii % MOD;
        return ascii;
    }
}
int main()
{
    fstream f;
    SymbolTable Table;
    f.open("code.txt");
    while(f){
        string cmd, id, na;
        f>>cmd;

        if(cmd == "I"){

            f>>id>>na;
            Symbolinfo sym = Symbolinfo(id, na);

            int hValue = hashFunction(id);
            bool flag = true;
            for(int i = 0; i < Table.table[hValue].size(); i++){
                if(sym.identifier == Table.table[hValue][i].identifier){
                    cout<<"Identifier exists"<<endl;
                    flag = false;
                }
            }
            if(flag == true){
                Table.table[hValue].push_back(sym);
                cout<< "<" << na << "," << id << "> Inserted at position(" << hValue << "," << Table.table[hValue].size() << ")" << endl;
            }
        }

        else if(cmd == "P")
        {
            int i = 0;
            while(i < SIZE)
            {
                cout<<i<<" ->";
                for(int j = 0; j < Table.table[i].size(); j++){
                    cout<<"<"<<Table.table[i][j].identifier<<","<<Table.table[i][j].name<<">";
                }
                cout<<endl;
                i++;

            }
        }
        else if(cmd == "D")
        {
            string l;
            f>>l;
            int hValue = hashFunction(l);


                for(int j =0; j < Table.table[hValue].size(); j++){
                    if(Table.table[hValue][j].identifier == l){
                        Table.table[hValue].erase(Table.table[hValue].begin()+j);
                    }
                    cout<<"Deleted"<<endl;
                }

        }
        else if(cmd == "L")
        {
            string l;
            f>>l;
            int hValue = hashFunction(l);
            for(int j =0; j < Table.table[hValue].size(); j++){
                    if(Table.table[hValue][j].identifier == l){
                            cout<<"Found at "<<hValue<<","<<j<<endl;
                    }
                }

        }

    }
    f.close();
    return 0;
}