View Compilation Error

0_0_27777543_30752.cpp: In function 'void quick_sort(int*, int, int)':
0_0_27777543_30752.cpp:9:7: error: 'xx' was not declared in this scope
       xx = rand()%(r - l + 1);
       ^
0_0_27777543_30752.cpp:10:14: error: 'll' was not declared in this scope
       swap(a[ll],a[])
              ^
0_0_27777543_30752.cpp:10:20: error: expected primary-expression before ']' token
       swap(a[ll],a[])
                    ^
0_0_27777543_30752.cpp:12:18: error: 'rr' was not declared in this scope
       while(ll < rr){
                  ^
0_0_27777543_30752.cpp:13:24: error: 'key' was not declared in this scope
         while(a[rr] >= key && ll < rr) rr--; a[ll] = a[rr];
                        ^
0_0_27777543_30752.cpp:14:24: error: 'key' was not declared in this scope
         while(a[ll] <= key && ll < rr) ll++; a[rr] = a[ll];
                        ^
0_0_27777543_30752.cpp:16:15: error: 'key' was not declared in this scope
       a[ll] = key;
               ^