#include<stdio.h>

#define A_MIN 850

#define B_MIN 750

#define C_MIN 650

#define D_MIN 550

#define A_MAX 925

#define A 876

#define B_MAX 824

#define B 776

#define C_MAX 724

#define C 676

#define D_MAX 624

#define D 576


int main(void)

{

  int totalp;// Total points earned by student

  char courseg;// Grade earned by student

  int gradp;//  grade point for determining letter grade

  char sign;// additional sign for grade

  printf("Enter the total points earned :  ");

  scanf("%d",&totalp);

  gradp = totalp / A_MIN;

  gradp += totalp / B_MIN;

  gradp += totalp / C_MIN;

  gradp += totalp / D_MIN;

  courseg = 'F' - gradp;

  courseg -= totalp/ D_MIN;

  sign = totalp / A_MAX;

  sign += totalp / A;

  sign += totalp / A_MIN;

  sign += totalp / B_MAX;

  sign += totalp / B;

  sign += totalp / B_MIN;

  sign += totalp / C_MAX;

  sign += totalp / C;

  sign += totalp / C_MIN;

  sign += totalp / D_MAX;

  sign += totalp / D;

  sign += totalp / D_MIN;

  sign % 3;
  sign = sign -2;
  sign =(-1)*sign;
  sign = sign * 2;

  printf("Course Grade Earned: %c%c\n",courseg,sign);
  return(0);
}

성적 점수에 따라서 a+ a a- 이렇게 나오도록하는건데요.. 부호 넣는거에서 멘붕이 오네요..