Switch Statement Vs if-else statement

Question

Lets say I want to write a program that asks users for a score (0-100) and assign a letter grade (A-E) to the score, is it possible to use a switch statement (without having 101 cases) or if-else statement is better?
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.
.
int score;
if ((score >= 80) && (score < 90))
cout << "You've got a B\n";
else if ((score >= 70) && (score < 80))
cout << "You've got a C\n";
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Answer 1

If you need to check ranges (like you would do for a grading system), you must use if/else. A switch only checks for specific, single values.

Answer 2

with GCC and LLVM/Clang, both support ranges in switch case statement. Not sure if this is in the language standard or just compiler extension.

Here is how it looks:

switch(marks){
case 1 ... 49: printf("fail"); break;
case 50 ... 64: printf("credit"); break;
...
...
}

Answer 3

With a switch, you can run the same code for multiple cases, but you can't include an inequality/range.

switch(score){
case 1:
case 2:
case 3:
grade = "C";
break;
case 4:
case 5:
case 6:
grade = "B";
break;
default:
grade = "A";
}

OR

if (score < 4){
grade = "C";
}
else if (score < 7){
grade = "B";
}
else {
grade = "A"
}

Seems like the if else statements are easier.