for (unsigned int i=heapsize/2-1; i>=0;-I.)

The representation of the unsigned int
Today, I encountered a bug when I wrote the heap sort.

  
 

   
  

  
void builMaxHeap( int *arr,unsigned int heapSize){
   
  

  
unsigned int i; 
   
  

  
for(i=heapSize/2-1; i>=0;--i){
   
  

  
std::cout<<i<<std::endl; 
   
  

  
//maxHeap(arr,i,heapSize); 这里暂且注释掉
   
  

  
}
   
  

  
}
  
 

This is really the whole dead man, thought it was the wrong program, the output of the result is
Hehe, can only hehe, the reason is that we use the unsigned unsigned int type to represent I

 
   
  

  
    
   
for(i=heapSize/2-1; i>=0;--i){
 
   
  

In other words, if I is a negative number, exit the loop, unfortunately Ah, for unsigned type I is never end to get negative AH!!!! A typical death





From for notes (Wiz)

= 0; -i), mamicode.com "style=" color: #ffffff "target=" _blank ">for (unsigned int i=heapsize/2-1; i>=0;-I.)