Проблема с флагами js

(function() { 
  let flag = true; 
  let item = [document.getElementById("item0"), document.getElementById("item1")]; 
 
  //---------------------------------------------------------------- 
  function c(str) { 
    console.log('Entered c...'); 
  } 
  //---------------------------------------------------------------- 
 
  document.addEventListener("click", function(e) { 
 
    if (e.target.classList.contains('link')) { 
 
      if (flag ? item[0] : item[1]) { 
        c("0"); 
      } else { 
        c("1"); 
      } 
      flag = !flag; 
      console.log(flag); // debugg 
    } 
  }); 
})();

<!-------- Doesn't have class link --------> 
<h1 id="item0" class="item00">Div 1</h1> 
<h1 id="item1">Div 2</h1> 
<!-------- Has class link --------> 
<div class="link">With link class</div>

(function() { 
  let flag = true; 
  let item = [document.getElementById("item0"), document.getElementById("item1")]; 
 
  //---------------------------------------------------------------- 
  function c(index) { 
     // Hide/Show current element 
    item[index].classList.add('show'); 
    item[index].classList.remove('hide'); 
    // Hide other element 
    item[index ? 0 : 1].classList.add('hide'); 
 
  } 
  //---------------------------------------------------------------- 
 
  document.addEventListener("click", function(e) { 
    if (e.target.classList.contains('link')) { 
      if (flag) { 
        c(0); 
      } else { 
        c(1); 
      } 
      flag = !flag; 
    } 
  }); 
})();

.hide { 
  visibility: hidden; 
} 
 
.show { 
  display: block; 
} 
 
.link { 
  cursor: pointer; 
  color: orange; 
}

<!-------- Doesn't have class link --------> 
<h1 id="item0" class="hide">Div 1</h1> 
<h1 id="item1">Div 2</h1> 
<!-------- Has class link --------> 
<div class="link">With link class</div>

(function (){ 
  let flag = true; 
  let items = [document.getElementById("item0"), document.getElementById("item1")]; 
  document.addEventListener("click", function(e) { 
    if (e.target.classList.contains('link')) { 
      e.preventDefault();  
      addText(items[+(flag = !flag)], e.target.textContent);  // +Bool === 0 или 1 (Number)  
    } 
  }); 
 
  function addText(elem, str) { 
    elem.insertAdjacentHTML('beforeend', ` 
      <span class="item-sub">${str}</span>  
    `);  
    console.clear();  
    console.log(`Текст "${str}" добавлен в #${elem.id}`);  
  } 
})();

h1 { padding: 0.2em 0.2em 0.2em 0.7em; line-height: 1em; min-height: 1em; background-color: #eee; box-shadow: inset 0 3px 5px 0 #0004; } 
h1:nth-of-type(n+2) { margin-top: -0.5em; } 
.item-sub { margin-left: -0.5em; } 
.link { font-size: 32px; text-decoration: none; margin-right: 0.5em; padding: 0 0.5em; border: 1px solid #ccc; } 
.link:before { content: '+'; display: inline; }

<a href="#" class="link">