View Compilation Error

0_0_14668223_30681.c: In function 'main':
0_0_14668223_30681.c:4:5: error: unknown type name 'bool'
     bool flag=true;
     ^
0_0_14668223_30681.c:4:15: error: 'true' undeclared (first use in this function)
     bool flag=true;
               ^
0_0_14668223_30681.c:4:15: note: each undeclared identifier is reported only once for each function it appears in
0_0_14668223_30681.c:12:18: error: 'false' undeclared (first use in this function)
             flag=false;
                  ^