Problem
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.
Constraints
0 ≤ score ≤ 100
Examples
Example 1
Input:
score = 85
Expected output:
expected = "B"Input:
long long score = 85;
Expected output:
std::string expected = "B";Input:
long score = 85;
Expected output:
string expected = "B";Explanation
85 is at least 80 but below 90, so the grade is B.
Example 2
Input:
score = 59
Expected output:
expected = "F"Input:
long long score = 59;
Expected output:
std::string expected = "F";Input:
long score = 59;
Expected output:
string expected = "F";Explanation
59 is below 60, so the grade is F.
References
This challenge is adapted for CodeUtility. Follow the statement and constraints above.