function showSolution(idArg) {
    if (document.getElementById(idArg) != null) {
    
      if (document.getElementById(idArg).style.display == 'inline') {
        document.getElementById(idArg).style.display = 'none';
      } else {
        document.getElementById(idArg).style.display = 'inline';
      }
      
    } // ends 'if' null
}





function checkSolution(formIdArg) {
  // gets element by id (expected only 'form')
  var x = document.getElementById(formIdArg);  
  if (x != null) {

  // if first element is displayed than hide previous solutions
  if (document.getElementById(formIdArg + '-correct-1').style.display == 'inline' || document.getElementById(formIdArg + '-wrong-1').style.display == 'inline') {
  
        // hides previous solutions
        for (var i = 0; i < x.length; i++) {
           document.getElementById(formIdArg + '-correct-' + (i + 1)).style.display = 'none';
           document.getElementById(formIdArg + '-wrong-' + (i + 1)).style.display = 'none';  
        }  
  
  } else {
  
        // cycles through all elements (expected only 'select')     
        for (var i = 0; i < x.length; i++) {
        
          var sel = x.elements[i];
          // cyclese through all options
          for (var j = 0; j < sel.length; j++) {
            // if is set class name to true and the option is selected than it was correct answer
            if (sel.options[j].className == 'true' && sel.selectedIndex == j) {
                document.getElementById(formIdArg + '-correct-' + (i + 1)).style.display = 'inline';
                j = sel.length;
            } else {
              if (j == sel.length - 1) {
                document.getElementById(formIdArg + '-wrong-' + (i + 1)).style.display = 'inline';  
              }      
            }
          }
          
        }  
  
  } // ends 'if' for hide (or not) solution  
  
         
} // ends 'if' null
}



  


function checkSolution2(formIdArg) {
  // gets element by id (expected only 'form')
  var x = document.getElementById(formIdArg);   
  if (x != null) {
  
  
   
  // if first element is displayed than hide previous solutions
  if (document.getElementById(formIdArg + '-correct-1').style.display == 'inline' || document.getElementById(formIdArg + '-wrong-1').style.display == 'inline') {

        // hides previous solutions
        for (var i = 0; i < x.length; i++) {
           document.getElementById(formIdArg + '-correct-' + (i + 1)).style.display = 'none';
           document.getElementById(formIdArg + '-wrong-' + (i + 1)).style.display = 'none'; 
        }    
          
  } else {

        // cycles through all elements (expected only 'input')     
        for (var i = 0; i < x.length; i++) {
        
          var input = x.elements[i];
      
            // if is set class name to true and the option is selected than it was correct answer
            if (input.name == input.value) {
                document.getElementById(formIdArg + '-correct-' + (i + 1)).style.display = 'inline';
      
            } else {
                document.getElementById(formIdArg + '-wrong-' + (i + 1)).style.display = 'inline';  
            }       
        } 
  
  } // ends 'if' for hide (or not) solution   
} // ends 'if' null           

}












function showAll(showSolutionLastKey, checkSolutionArray, checkSolution2Array) {  
      
     elementVse = document.getElementById('odkaz-vse'); 
 
     if(elementVse.className == "switchoff") {     
	       elementVse.innerHTML = "<strong>Skrýt řešení</strong><br />všech příkladů";  
	       elementVse.className = "switchon";   
                        
     } else {         
	       elementVse.innerHTML = "<strong>Zobrazit řešení</strong><br />všech příkladů";  
	       elementVse.className = "switchoff";   
	   }    
        
    
    // FIRST WE MUST HIDE ALL EVERYTIME 
        
    // cycles through all elements from "showSolutionArray" and hides them 
    for (var i = 0; i < showSolutionLastKey; i++) {    
       if ((i+1) < 10) {                    
          if(document.getElementById("klic0" + (i+1)) != null) { document.getElementById("klic0" + (i+1)).style.display = 'none'; }
       } else {          
          if(document.getElementById("klic" + (i+1)) != null) { document.getElementById("klic" + (i+1)).style.display = 'none'; 
       }  
       } 
    }
        
                
                                
 
    
     // cycles through all elements from "showSolutionArray" and hides them      
     for (var i = 0; i < checkSolutionArray.length; i++) {
            var x = document.getElementById(checkSolutionArray[i]); 
            if (x != null) {   
              // hides previous solutions
              for (var j = 0; j < x.length; j++) {    
                document.getElementById(checkSolutionArray[i] + '-correct-' + (j + 1)).style.display = 'none';
                document.getElementById(checkSolutionArray[i] + '-wrong-' + (j + 1)).style.display = 'none';   
              }   
            } 
      }           
    
     // cycles through all elements from "showSolutionArray" and shows them     
     for (var i = 0; i < checkSolution2Array.length; i++) {              
            var x = document.getElementById(checkSolution2Array[i]); 
            if (x != null) {        
              // hides previous solutions
              for (var j = 0; j < x.length; j++) {
                document.getElementById(checkSolution2Array[i] + '-correct-' + (j + 1)).style.display = 'none';
                document.getElementById(checkSolution2Array[i] + '-wrong-' + (j + 1)).style.display = 'none'; 
              }
            }  
      }
             
    
    
    
    
    // IF SWITCH IS ON THEN WE MUST SHOW ALL      
    if (elementVse.className == "switchon") {
        // cycles through all elements from "showSolutionArray" and shows them    
        for (var i = 0; i < showSolutionLastKey; i++) {  
           if ((i+1) < 10) {                    
              if(document.getElementById("klic0" + (i+1)) != null) { document.getElementById("klic0" + (i+1)).style.display = 'none'; 
              showSolution("klic0" + (i+1));
              }
           } else {          
              showSolution("klic" + (i+1));  
           }        
        }    
                 
  
        
         // cycles through all elements from "showSolutionArray" and shows them      
        for (var i = 0; i < checkSolutionArray.length; i++) {
           checkSolution(checkSolutionArray[i]); 
        }
            
        
         // cycles through all elements from "showSolutionArray" and shows them      
        for (var i = 0; i < checkSolution2Array.length; i++) {
           checkSolution2(checkSolution2Array[i]); 
        }      
    } // ends 'if' for switch       
          
               
}















/*#############################################################x*/    
/*######################## POSUN OVLÁDÁNÍ #####################x*/
/*#############################################################x*/


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		var scrollingTrigger;
		var fixed = false;
		
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			flowBlockHeight = document.getElementById("swmaster").scrollHeight;
      scrollingTrigger = 250 + menuHeight + document.getElementById("swmaster").style.marginTop;  
			setFlowBlock();
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			setFlowBlock();		
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    function getScrolled() {
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    			//DOM compliant
    			scrolled = document.body.scrollTop;
  			} else if(document.documentElement && document.documentElement.scrollTop) {
    			//IE6 standards compliant mode
    			scrolled = document.documentElement.scrollTop;
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  			return scrolled;    
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		function setFlowBlock() {     		
			if ( !fixed && (getScrolled() > scrollingTrigger)) {
        document.getElementById("swmaster").className = "positionFixed";        
				fixed = true;  
			} else if (fixed && (getScrolled() <= scrollingTrigger)) {
        document.getElementById("swmaster").className = "positionNormal";              
				fixed = false;  
			}  
    }

   */