View Compilation Error

0_0_22487263_25151.cpp: In function 'int main(int, const char**)':
0_0_22487263_25151.cpp:57:3: error: 'a' was not declared in this scope
   a = b = 0;
   ^
0_0_22487263_25151.cpp:57:7: error: 'b' was not declared in this scope
   a = b = 0;
       ^