View Compilation Error

0_0_25784144_31941.cpp:1:1: error: 'include' does not name a type
 include<bits/stdc++.h>
 ^
0_0_25784144_31941.cpp: In function 'int main()':
0_0_25784144_31941.cpp:7:18: error: 'scanf' was not declared in this scope
     scanf("%d",&t);
                  ^
0_0_25784144_31941.cpp:12:25: error: 'atan' was not declared in this scope
         double du=atan(k);
                         ^
0_0_25784144_31941.cpp:15:32: error: 'cos' was not declared in this scope
         double high1=cha*cos(du);
                                ^
0_0_25784144_31941.cpp:16:43: error: 'sqrt' was not declared in this scope
         double t1=sqrt(2*high1/(g*cos(du)));
                                           ^
0_0_25784144_31941.cpp:17:48: error: 'sin' was not declared in this scope
         double xie=sqrt(x*x+k*x*k*x)+cha*sin(du);
                                                ^
0_0_25784144_31941.cpp:30:30: error: 'printf' was not declared in this scope
         printf("%lld\n",times);
                              ^