grade

#include<stdio.h>
#include<conio.h>
void main()
{
	int C,CF,DM,ST,EN;
	float total,score;
	char Grade,cfG,cG,Name[10];
	clrscr();
	printf("Enter name of student: ");
	scanf("%s",&Name);
	printf("\nEnter mark of C: ");
	scanf("%d",&C);
	if(C<0 && C>100)
		printf("Re enter Mark");
	if(C>=90)
		cG='A';
	else if(C>=80 && C<=89)
		cG='B';
	else if(C>=70 && C<=79)
		cG='C';
	else if(C>=60 && C<=69)
		cG='D';
	else if(C>=50 && C<=59)
		cG='E';
	else if(C<50)
		cG='F';
	else
		printf("INVALID ENTRY");


	printf("\nEnter mark of CF: ");
	scanf("%d",&CF);
	if(CF<0 && CF>100)
		printf("CF<0 && CF>100");
	if(CF>=90)
		cfG='A';
	else if(CF>=80 && CF<=89)
		cfG='B';
	else if(CF>=70 && CF<=79)
		cfG='C';
	else if(CF>=60 && CF<=69)
		cfG='D';
	else if(CF>=50 && CF<=59)
		cfG='E';
	else if(CF<50)
		cfG='F';
	else
		printf("INVALID ENTRY");

	printf("\nEnter mark of DM: ");
	scanf("%d",&DM);
	if(DM<0 && DM>100)
		printf("Re enter Mark");
	printf("\nEnter mark of ST: ");
	scanf("%d",&ST);
	if(ST<0 && ST>100)
		printf("Re enter Mark");
	printf("\nEnter mark of EN: ");
	scanf("%d",&EN);
	if(EN<0 && EN>100)
		printf("Re enter Mark");
	total=EN+ST+DM+C+CF;
	score=total/5;
	printf("\nName of the student:%s",Name);
	printf("\nGrade of C=%c",cG);
	printf("\nGrade of CF=%c",cfG);
	if(score>=90)
		printf("\nGrade of the student= A");
	else if(score>=80 && score<=89)
		printf("\nGrade of the student= B");
	else if(score>=70 && score<=79)
		printf("\nGrade of the sudent= C");
	else if(score>=60 && score<=69)
		printf("\nGrade of the student= D");
	else if(score>=50 && score<=59)
		printf("\nGrade of the student= E");
	else if(score<50)
		printf("\nGrade of the student= F");
	else
		printf("Invalid Entry");

	getch();
}