View Compilation Error

0_0_33975672_26418.cpp: In function 'void Min25::init()':
0_0_33975672_26418.cpp:31:25: error: 'sqrt' was not declared in this scope
         T = sqrt(n + 0.5);
                         ^
0_0_33975672_26418.cpp: In function 'int main()':
0_0_33975672_26418.cpp:69:27: error: 'scanf' was not declared in this scope
     int t; scanf("%d" , &t);
                           ^
0_0_33975672_26418.cpp:79:29: error: 'printf' was not declared in this scope
         printf("%lld\n", ans);
                             ^