View Compilation Error

0_0_1599986_32151.cpp:4: error: expected namespace-name before ';' token
0_0_1599986_32151.cpp:4: error: `<type error>' is not a namespace
0_0_1599986_32151.cpp: In function `int main()':
0_0_1599986_32151.cpp:14: error: `sort' undeclared (first use this function)
0_0_1599986_32151.cpp:14: error: (Each undeclared identifier is reported only once for each function it appears in.)