Quy ước viết mã

#include <stdio.h>
#include <stdlib.h>
struct Diem{int x;int y;};
typedef struct{char ten[32];int tuoi;double diem;}SinhVien;
int  tong( int *a,int n ){int s=0;for(int i=0;i<n;i++){s+=a[i];}return s;}
static void in( SinhVien *sv,int n )
{
for(int i=0;i<n;i++)
{
if(sv[i].diem>=8.0){printf("%s: gioi\n",sv[i].ten);}
else if(sv[i].diem>=6.5) printf("%s: kha\n",sv[i].ten);
    else {
        printf("%s: trung binh\n",sv[i].ten);
    }
}
}
int main(void){SinhVien sv[]={{"an",20,8.5},{"binh",21,7.0},{"chi",20,5.5}};
int a[]={1,2,3,4,5};
printf("%d\n",tong(a,5));in(sv,3);return 0;}

#include <stdio.h>
#include <stdlib.h>
struct Diem {
    int x;
    int y;
};
typedef struct {
    char   ten[32];
    int    tuoi;
    double diem;
} SinhVien;
int tong(int *a, int n) {
    int s = 0;
    for (int i = 0; i < n; i++) {
        s += a[i];
    }
    return s;
}
static void in(SinhVien *sv, int n) {
    for (int i = 0; i < n; i++) {
        if (sv[i].diem >= 8.0) {
            printf("%s: gioi\n", sv[i].ten);
        } else if (sv[i].diem >= 6.5)
            printf("%s: kha\n", sv[i].ten);
        else {
            printf("%s: trung binh\n", sv[i].ten);
        }
    }
}
int main(void) {
    SinhVien sv[] = {{"an", 20, 8.5}, {"binh", 21, 7.0}, {"chi", 20, 5.5}};
    int      a[] = {1, 2, 3, 4, 5};
    printf("%d\n", tong(a, 5));
    in(sv, 3);
    return 0;
}

---
Language:        Cpp                  # C dung chung bo may voi C++
BasedOnStyle:    LLVM                 # nen tang, roi ghi de ben duoi
IndentWidth:     4
ColumnLimit:     88
AlignConsecutiveDeclarations: true    # can le cot ten bien
AlignConsecutiveAssignments:  false
AllowShortFunctionsOnASingleLine: None
AllowShortIfStatementsOnASingleLine: Never
AllowShortLoopsOnASingleLine: false
BreakBeforeBraces: Attach             # ngoac mo cung dong
PointerAlignment: Right               # char *s, khong phai char* s
SpaceAfterCStyleCast: false
SortIncludes:    true

root = true

[*]
charset = utf-8
end_of_line = lf
insert_final_newline = true
trim_trailing_whitespace = true
indent_style = space
indent_size = 4

[*.{c,h}]
indent_size = 4
max_line_length = 88

[Makefile]
indent_style = tab          # Make BAT BUOC dung tab

[*.{yml,yaml,json}]
indent_size = 2

[*.md]
trim_trailing_whitespace = false   # hai dau cach cuoi dong = xuong dong

SRC := $(shell find src include -name '*.c' -o -name '*.h')

.PHONY: dinh-dang kiem-dinh-dang

dinh-dang:
	clang-format -i $(SRC)

kiem-dinh-dang:
	clang-format --dry-run -Werror $(SRC)

kiem-tra: kiem-dinh-dang canh-bao kiem-thu

name: kiem tra
on: [push, pull_request]

jobs:
  dinh-dang:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: cai clang-format
        run: sudo apt-get update && sudo apt-get install -y clang-format
      - name: kiem tra dinh dang
        run: clang-format --dry-run -Werror $(git ls-files '*.c' '*.h')

  dung-va-kiem-thu:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: make kiem-tra