View Compilation Error

0_0_2189406_29720.cpp: In function `int main()':
0_0_2189406_29720.cpp:16: error: `a' undeclared (first use this function)
0_0_2189406_29720.cpp:16: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_2189406_29720.cpp:29: error: expected primary-expression before '}' token
0_0_2189406_29720.cpp:29: error: expected `;' before '}' token
0_0_2189406_29720.cpp:29: error: expected primary-expression before '}' token
0_0_2189406_29720.cpp:29: error: expected `;' before '}' token
0_0_2189406_29720.cpp:29: error: expected primary-expression before '}' token
0_0_2189406_29720.cpp:29: error: expected `)' before '}' token
0_0_2189406_29720.cpp:29: error: expected primary-expression before '}' token
0_0_2189406_29720.cpp:29: error: expected `;' before '}' token