Problème
Convert a score from 0 to 100 into a letter grade: 90 and above is A, 80–89 is B, 70–79 is C, 60–69 is D, and below 60 is F.
Implement letter_grade(score).
Input
score: The test score.
Output
Return the letter as a one-character string.
Contraintes
0 ≤ score ≤ 100
Exemples
Exemple 1
Entrée :
score = 85
Sortie attendue :
expected = "B"Entrée :
long long score = 85;
Sortie attendue :
std::string expected = "B";Entrée :
long score = 85;
Sortie attendue :
string expected = "B";Explication
85 is at least 80 but below 90, so the grade is B.
Exemple 2
Entrée :
score = 59
Sortie attendue :
expected = "F"Entrée :
long long score = 59;
Sortie attendue :
std::string expected = "F";Entrée :
long score = 59;
Sortie attendue :
string expected = "F";Explication
59 is below 60, so the grade is F.
Comment l'aborder
Essayez d'abord seul, puis ouvrez les indices un par un.
Indice 1
Compare the score against the highest passing threshold first and work downward.
Indice 2
A chain of ordered comparisons is the simplest way to map ranges to letters.
Indice 3
Make sure boundary scores like 90, 80, 70, and 60 fall into the higher grade band.
Complexité attendue
O(1) time, O(1) extra space
Références
Ce défi a été adapté pour CodeUtility. Suivez l'énoncé et les contraintes ci-dessus.