Compilare: user.cpp: In function ‘void update_pi()’: user.cpp:25:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] FOR(i, 2, P.sz() - 1){ ^ user.cpp:6:42: note: in definition of macro ‘FOR’ #define FOR(i, x, y) for(int i = x; i <= y; ++i) ^ user.cpp: In function ‘void kmp(int)’: user.cpp:34:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] FOR(i, 1, T.sz() - 1){ ^ user.cpp:6:42: note: in definition of macro ‘FOR’ #define FOR(i, x, y) for(int i = x; i <= y; ++i) ^ user.cpp: In function ‘int main()’: user.cpp:61:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] FOR(k, 1, T.sz() -1){ ^ user.cpp:6:42: note: in definition of macro ‘FOR’ #define FOR(i, x, y) for(int i = x; i <= y; ++i) ^ user.cpp:47:15: warning: variable ‘ans’ set but not used [-Wunused-but-set-variable] int t, n, ans, s; ^ user.cpp:47:20: warning: unused variable ‘s’ [-Wunused-variable] int t, n, ans, s; ^