text: import React from 'react';
  import { Link } from 'react-router-dom';
  import { HashLink } from 'react-router-hash-link';
  import { logo } from './Constants';
  
  
  const Navigation = () => (
    <nav className="navbar fixed-top navbar-expand-lg navbar-dark bg-dark">
      <HashLink className="navbar-brand" to="/#">
        <img src={logo} width="40" height="40" alt="logo" />
      </HashLink>
      <button
        className="navbar-toggler"
        type="button"
        data-toggle="collapse"
        data-target="#navbarNav"
        aria-controls="navbarNav"
        aria-expanded="false"
        aria-label="Toggle navigation"
      >
        <span className="navbar-toggler-icon" />
      </button>
      <div className="collapse navbar-collapse" id="navbarNav">
        <ul className="nav navbar-nav">
          <li className="nav-item active">
            <HashLink smooth to="/#">
              <span className="nav-link">
                Home
                {' '}
                <span className="sr-only">(current)</span>
              </span>
            </HashLink>
          </li>
          <li className="nav-item">
            <HashLink smooth to="/#what-we-do">
              <span className="nav-link">What we provide?</span>
            </HashLink>
          </li>
          <li className="nav-item">
            <HashLink smooth to="/#contributors">
              <span className="nav-link">Contributors</span>
            </HashLink>
          </li>
          <li className="nav-item">
            <Link to="/aboutus">
              <span className="nav-link" href="/aboutus">
                About
              </span>
            </Link>
          </li>
        </ul>
        <ul className="nav navbar-nav navbar-right ml-md-auto ">
          <li className="nav-item">
            <a
              className="nav-link"
              rel="noopener noreferrer"
              target="_blank"
              href="https://bit.ly/2NwWLhp"
            >
              Join
            </a>
          </li>
          <li className="nav-item dropdown">
            <a
              className="nav-link dropdown-toggle"
              href="#"
              id="navbarDropdownMenuLink"
              data-toggle="dropdown"
              aria-haspopup="true"
              aria-expanded="false"
            >
              Sign in
            </a>
            <div
              className="dropdown-menu"
              aria-labelledby="navbarDropdownMenuLink"
            >
              <Link to="/login/student">
                <span className="dropdown-item">Student</span>
              </Link>
              <Link to="/login/professor">
                <span className="dropdown-item">Professor</span>
              </Link>
            </div>
          </li>
          <li className="nav-item dropdown">
            <a
              className="nav-link dropdown-toggle"
              href="#"
              id="navbarDropdownMenuLink"
              data-toggle="dropdown"
              aria-haspopup="true"
              aria-expanded="false"
            >
              Sign up
            </a>
            <div
              className="dropdown-menu dropdown-menu-right"
              aria-labelledby="navbarDropdownMenuLink"
            >
              <Link to="/signup/student">
                <span className="dropdown-item">Student</span>
              </Link>
              <Link to="/signup/professor">
                <span className="dropdown-item">Professor</span>
              </Link>
            </div>
          </li>
        </ul>
      </div>
    </nav>
  );
  export default Navigation;
  