Skip to content

Make the getPrec function simpler and more efficient #20

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
RHL120 wants to merge 3 commits into
base: master
Choose a base branch
from
Open

Make the getPrec function simpler and more efficient #20

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
8c507f3
Make the getPrec function simpler and more efficient
RHL120 Feb 6, 2023
eb82550
Remove the stdio include
RHL120 Feb 6, 2023
b197de7
Fix the failing tests due to the getPrec modifications
RHL120 Feb 6, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
26 changes: 4 additions & 22 deletions src/lexer.c
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,4 +1,5 @@
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
Expand Down Expand Up @@ -268,29 +269,10 @@ void initList(struct list **list)

int getPrec(enum OPCODE opcode)
{
if (opcode == OP_Equal) {
return 5;
int prec[] = {5, 4, 4, 3, 3, 2, 2, 1};
if (opcode < sizeof(prec) / sizeof(int)) {
return prec[opcode];
}

if (opcode == OP_Open_parenthesis ||
opcode == OP_Closed_parenthesis) {
return 4;
}

if (opcode == OP_Plus ||
opcode == OP_Minus) {
return 3;
}

if (opcode == OP_Multi ||
opcode == OP_Div) {
return 2;
}

if (opcode == OP_Pow) {
return 1;
}

return 0;
}

Expand Down
7 changes: 4 additions & 3 deletions src/lexer.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -10,12 +10,15 @@ enum TOKEN_TYPE {
T_None
};

// A change to this enum should be coupled with a change to getPrec in lexer.c
enum OPCODE {
OP_Equal,
OP_Open_parenthesis,
OP_Closed_parenthesis,
OP_Plus,
OP_Minus,
OP_Multi,
OP_Div,
OP_Equal,
OP_Pow,
OP_Fact,
OP_Sqrt,
Expand All @@ -35,8 +38,6 @@ enum OPCODE {
OP_Asin,
OP_Acos,
OP_Atan,
OP_Closed_parenthesis,
OP_Open_parenthesis,
OP_None,
};

Expand Down