/in/foo.c: In function 'main':
/in/foo.c:12:6: error: 'i' undeclared (first use in this function)
  for(i=0;i<N;i++)
      ^
/in/foo.c:12:6: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:12:12: error: 'N' undeclared (first use in this function)
  for(i=0;i<N;i++)
            ^
/in/foo.c:18:7: error: 'j' undeclared (first use in this function)
   for(j=0;j<n;j++)
       ^
/in/foo.c:35:2: error: unknown type name 'lunwen'
  lunwen *a={{44,20},{43,10},{56,12}};
  ^
/in/foo.c:35:10: error: redeclaration of 'a' with no linkage
  lunwen *a={{44,20},{43,10},{56,12}};
          ^
/in/foo.c:7:7: note: previous declaration of 'a' was here
  int *a,*b,n,m;
       ^
/in/foo.c:35:2: warning: braces around scalar initializer [enabled by default]
  lunwen *a={{44,20},{43,10},{56,12}};
  ^
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: initialization makes pointer from integer without a cast [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: excess elements in scalar initializer [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: braces around scalar initializer [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: initialization makes pointer from integer without a cast [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: excess elements in scalar initializer [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: excess elements in scalar initializer [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: braces around scalar initializer [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: initialization makes pointer from integer without a cast [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: excess elements in scalar initializer [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: warning: excess elements in scalar initializer [enabled by default]
/in/foo.c:35:2: warning: (near initialization for 'a') [enabled by default]
/in/foo.c:35:2: error: expected declaration or statement at end of input
/in/foo.c:35:10: warning: unused variable 'a' [-Wunused-variable]
  lunwen *a={{44,20},{43,10},{56,12}};
          ^