View Compilation Error

0_0_3091519_13417.cpp: In function `void solve()':
0_0_3091519_13417.cpp:47: error: `vector' undeclared (first use this function)
0_0_3091519_13417.cpp:47: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_3091519_13417.cpp:47: error: expected primary-expression before "int"
0_0_3091519_13417.cpp:47: error: expected `;' before "int"
0_0_3091519_13417.cpp:48: error: `Q' undeclared (first use this function)
0_0_3091519_13417.cpp:76: error: `area' undeclared (first use this function)
0_0_3091519_13417.cpp:76: error: `vol' undeclared (first use this function)
0_0_3091519_13417.cpp: In function `int main()':
0_0_3091519_13417.cpp:83: error: `N' undeclared (first use this function)