def get_grade(mark):
    if 91 <= mark <= 100:
        return 'S Grade'
    elif 81 <= mark <= 90:
        return 'A Grade'
    elif 71 <= mark <= 80:
        return 'B Grade'
    elif 61 <= mark <= 70:
        return 'C Grade'
    elif 51 <= mark <= 60:
        return 'D Grade'
    elif 41 <= mark <= 50:
        return 'E Grade'
    elif 0 <= mark <= 40:
        return 'F Grade'
    else:
        return 'Invalid Mark'

def main():
    marks = []
    for i in range(4):
        mark = int(input(f"Enter mark for subject {i+1}: "))
        marks.append(mark)

    print("\nGrades for each subject:")
    for i, mark in enumerate(marks, 1):
        grade = get_grade(mark)
        print(f"Subject {i}: {grade}")

if __name__ == "__main__":
    main()