View Compilation Error

0_0_3196126_14945.cpp: In function `int main()':
0_0_3196126_14945.cpp:12: error: `plus' undeclared (first use this function)
0_0_3196126_14945.cpp:12: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_3196126_14945.cpp: At global scope:
0_0_3196126_14945.cpp:15: error: expected constructor, destructor, or type conversion before '(' token
0_0_3196126_14945.cpp:15: error: expected `,' or `;' before '(' token
0_0_3196126_14945.cpp:18: error: expected unqualified-id before '{' token
0_0_3196126_14945.cpp:18: error: expected `,' or `;' before '{' token