View Compilation Error

0_0_1284140_3226.cpp: In function `int main()':
0_0_1284140_3226.cpp:5: error: expected init-declarator before '.' token
0_0_1284140_3226.cpp:5: error: expected `,' or `;' before '.' token
0_0_1284140_3226.cpp:6: error: `n' undeclared (first use this function)
0_0_1284140_3226.cpp:6: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_1284140_3226.cpp:7: error: `sum' undeclared (first use this function)