View Compilation Error

0_0_9716469_32382.cpp: In function `int main()':
0_0_9716469_32382.cpp:6: error: `doublt' undeclared (first use this function)
0_0_9716469_32382.cpp:6: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_9716469_32382.cpp:6: error: expected `;' before "r"
0_0_9716469_32382.cpp:8: error: `r' undeclared (first use this function)