View Compilation Error

0_0_30055979_16622.cpp: In function 'int main()':
0_0_30055979_16622.cpp:71:26: error: 'scanf' was not declared in this scope
     while (scanf("%d", &q) != EOF && q != 0) {
                          ^
0_0_30055979_16622.cpp:71:31: error: 'EOF' was not declared in this scope
     while (scanf("%d", &q) != EOF && q != 0) {
                               ^
0_0_30055979_16622.cpp:80:33: error: 'sort' was not declared in this scope
         sort(X + 1, X + 1 + tot1);
                                 ^
0_0_30055979_16622.cpp:82:39: error: 'unique' was not declared in this scope
         m = unique(X + 1, X + 1 + tot1) - X - 1;
                                       ^
0_0_30055979_16622.cpp:91:76: error: 'printf' was not declared in this scope
         printf("Test case #%d\nTotal explored area: %.2lf\n\n", kase++, ans);
                                                                            ^