View Compilation Error

0_0_2481931_26756.cpp:2: error: `__int64' does not name a type
0_0_2481931_26756.cpp:3: error: `main' must return `int'
0_0_2481931_26756.cpp: In function `int main(...)':
0_0_2481931_26756.cpp:5: error: `scanf' undeclared (first use this function)
0_0_2481931_26756.cpp:5: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_2481931_26756.cpp:7: error: `a' undeclared (first use this function)
0_0_2481931_26756.cpp:8: error: `sum' undeclared (first use this function)
0_0_2481931_26756.cpp:9: error: `mul' undeclared (first use this function)
0_0_2481931_26756.cpp:12: error: `w' undeclared (first use this function)
0_0_2481931_26756.cpp:14: error: `dp' undeclared (first use this function)
0_0_2481931_26756.cpp:15: error: `p' undeclared (first use this function)
0_0_2481931_26756.cpp:34: error: `printf' undeclared (first use this function)