View Compilation Error

0_0_4705767_31466.cpp: In function `void shuaxin()':
0_0_4705767_31466.cpp:21: error: `memset' undeclared (first use this function)
0_0_4705767_31466.cpp:21: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_4705767_31466.cpp: In function `bool spfa(int, int, int)':
0_0_4705767_31466.cpp:53: error: `memset' undeclared (first use this function)
0_0_4705767_31466.cpp:55: error: `priority_queue' undeclared (first use this function)
0_0_4705767_31466.cpp:55: error: expected primary-expression before '>' token
0_0_4705767_31466.cpp:55: error: `da' undeclared (first use this function)
0_0_4705767_31466.cpp: In function `int main()':
0_0_4705767_31466.cpp:163: error: `cout' undeclared (first use this function)
0_0_4705767_31466.cpp:163: error: `endl' undeclared (first use this function)