View Compilation Error

0_0_17019646_27817.c:7:6: error: conflicting types for 'pow'
 int  pow(int  a,int b)
      ^
In file included from 0_0_17019646_27817.c:2:0:
GCC4.9.2/x86_64-w64-mingw32/include/math.h:151:18: note: previous declaration of 'pow' was here
   double __cdecl pow(double _X,double _Y);
                  ^
0_0_17019646_27817.c: In function 'main':
0_0_17019646_27817.c:37:5: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
     for(int i=1;i<29399;i++)ans[i][0]=1;
     ^
0_0_17019646_27817.c:37:5: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code