View Compilation Error

0_0_5182270_12594.cpp: In function `bool pend(int)':
0_0_5182270_12594.cpp:9: error: `memset' undeclared (first use this function)
0_0_5182270_12594.cpp:9: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_5182270_12594.cpp: In function `int main()':
0_0_5182270_12594.cpp:38: error: `scanf' undeclared (first use this function)
0_0_5182270_12594.cpp:38: error: `EOF' undeclared (first use this function)
0_0_5182270_12594.cpp:55: error: `printf' undeclared (first use this function)