View Compilation Error

0_0_30504993_7188.cpp: In function 'int main()':
0_0_30504993_7188.cpp:53:32: error: 'min' was not declared in this scope
       if (flg) ans = min(ans, s);
                                ^
0_0_30504993_7188.cpp:57:49: error: 'min' was not declared in this scope
     if (t4 * t4 * t4 * t4 == n) ans = min(ans, 4);
                                                 ^
0_0_30504993_7188.cpp:58:39: error: 'min' was not declared in this scope
     if (t2 * t2 == n) ans = min(ans, 2);
                                       ^
0_0_30504993_7188.cpp:59:33: error: 'min' was not declared in this scope
     if (chk(n)) ans = min(ans, 3);
                                 ^