View Compilation Error

0_0_37988606_20445.cpp:15:1: error: expected ',' or ';' before 'int'
 int a[4][MAXN];
 ^
0_0_37988606_20445.cpp: In function 'bool work(int, int, int, int)':
0_0_37988606_20445.cpp:18:5: error: 'a' was not declared in this scope
  if(a[m][a[m][0]]==n){
     ^
0_0_37988606_20445.cpp:22:5: error: 'a' was not declared in this scope
  if(a[q][a[q][0]]==n){
     ^
0_0_37988606_20445.cpp: In function 'int main()':
0_0_37988606_20445.cpp:33:6: error: 'a' was not declared in this scope
   SI(a[1][0]);
      ^
0_0_37988606_20445.cpp:9:27: note: in definition of macro 'SI'
 #define SI(x) scanf("%d",&x)
                           ^