Finding grade and Average of a student |C code

#include<stdio.h> main() { int i,score,sum=0; int A=0,Bplus=0,B=0,Cplus=0,C=0,Dplus=0,D=0,F=0; for(i=1;i<=20;i++) { printf("Input Score %d:",i); scanf("%d",&score); sum=sum+score; if(score >=80) { A=A+1; }else if(score >=75) { Bplus=Bplus+1; }else if(score >=70) { B=B+1; }else if(score >=65) { Cplus=Cplus+1; }else if(score >=60) { C=C+1; }else if(score >=55) { Dplus=Dplus+1; }else if(score >=50) { D=D+1; }else { F=F+1; } } printf("Grade A=%d\n",A); printf("Grade B+=%d\n",Bplus); printf("Grade B=%d\n",B); printf("Grade C+=%d\n",Cplus); printf("Grade C=%d\n",C); printf("Grade D+=%d\n",Dplus); printf("Grade D=%d\n",D); printf("Grade F=%d\n",F); sum=sum/20; if(sum>=80) { printf("Grade Average is A\n"); }else if(sum>=75) { printf("Grade Average is B+\n"); }else if(sum>=70) { printf("Grade Average is B\n"); }else if(sum>=65) { printf("Grade Average is C+\n"); }else if(sum>=60) { printf("Grade Average is C\n"); }else if(sum>=55) { printf("Grade Average is D+\n"); }else if(sum>=50) { printf("Grade Average is D\n"); }else { printf("Grade Average is F\n"); } }