Off topic:R-Making Piechart By Groups

Question

[jackuser1979]

 id       sample(%) 
 R1       45   
 R2       25     
 R3       77   
 R4        0    
 R5      100   
  :
  :
 R10000   58

I want to create a pie chart in R by grouping on percentage with labels as shown in figure 0-20% 20-40% 40-60% 60-80% 80-100%