call.c

#include <stdio.h>

char grade (int score) {
    if (score >= 80) {
        return 'A';
    } else if (score >= 70) {
        return 'B';
    } else if (score >= 60) {
        return 'C';
    } else if (score >= 50) {
        return 'D';
    } else {
        return 'F';
    }
}

void line () {
    printf("==========================================\n");
}
title () {
	line();
	printf("Num\t\t Score\t\t Grade\n");
	line();
}
int main () {
	int score[5] ,i;
	char grades[5];

    for (i = 0; i < 5; i++) {
        printf("Input Score [%d] : ", i + 1);
        scanf("%d", &score[i]);
    }

    title();
	
    for (i = 0; i < 5; i++) {
        grades[i] = grade(score[i]);
        printf("%d\t\t %d\t\t %c\n", i + 1, score[i], grades[i]);
        line();
    }

    return 0;
}