View Compilation Error

0_0_10002511_23552.cpp:2: error: expected constructor, destructor, or type conversion before '<' token
0_0_10002511_23552.cpp:2: error: expected `,' or `;' before '<' token
0_0_10002511_23552.cpp: In function `int main()':
0_0_10002511_23552.cpp:21: error: `num' undeclared (first use this function)
0_0_10002511_23552.cpp:21: error: (Each undeclared identifier is reported only once for each function it appears in.)