View Compilation Error

0_0_33819856_8667.cpp: In function 'int main()':
0_0_33819856_8667.cpp:23:3: error: expected ';' before 'int'
   int r = 0;
   ^
0_0_33819856_8667.cpp:27:10: error: 'r' was not declared in this scope
     st[++r] = a[i], f[a[i]] = 1;
          ^