View Compilation Error

0_0_20381565_20871.cpp: In function 'void solve()':
0_0_20381565_20871.cpp:15:39: error: 'getchar_unlocked' was not declared in this scope
         while ((ch = getchar_unlocked()) != '\n') {
                                       ^
0_0_20381565_20871.cpp:28:76: error: 'putc_unlocked' was not declared in this scope
             for (int j = i - n + 1; j <= i; j++) putc_unlocked(s[j], stdout);
                                                                            ^
0_0_20381565_20871.cpp:29:39: error: 'putc_unlocked' was not declared in this scope
             putc_unlocked('\n', stdout);
                                       ^