View Compilation Error

0_0_33238310_25303.c:5:1: error: unknown type name 'bool'
 bool isprime[]={0,1,1,1,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,1,0,0};
 ^
0_0_33238310_25303.c:6:1: error: unknown type name 'bool'
 bool vis[20];
 ^
0_0_33238310_25303.c: In function 'dfs':
0_0_33238310_25303.c:29:18: error: 'true' undeclared (first use in this function)
         vis[i] = true;
                  ^
0_0_33238310_25303.c:29:18: note: each undeclared identifier is reported only once for each function it appears in
0_0_33238310_25303.c:32:18: error: 'false' undeclared (first use in this function)
         vis[i] = false;
                  ^