View Compilation Error

0_0_38787846_28743.cpp: In function 'void Merge(ll, ll, ll)':
0_0_38787846_28743.cpp:6:22: error: 'q' was not declared in this scope
    6 |         ll i=l,j=mid+q,t=0;
      |                      ^
0_0_38787846_28743.cpp:9:27: error: 't' was not declared in this scope
    9 |                         b[t++]=a[j++];
      |                           ^
0_0_38787846_28743.cpp:11:25: error: 't' was not declared in this scope
   11 |                 }else b[t++]=a[i++];
      |                         ^
0_0_38787846_28743.cpp:14:25: error: 't' was not declared in this scope
   14 |         while(i<=mid) b[t++]=a[i++];
      |                         ^
0_0_38787846_28743.cpp:15:23: error: 't' was not declared in this scope
   15 |         while(j<=r) b[t++]=a[j++];
      |                       ^
0_0_38787846_28743.cpp:16:19: error: 't' was not declared in this scope
   16 |         for(i=0;i<t;i++)  a[l+i]=b[i]; //把排好序的b[]复制回a[]
      |                   ^