Compilare: user.cpp: In function ‘int main()’: user.cpp:80:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < ctcuri.size(); ++i) { ^ user.cpp:81:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < ctcuri[i].size(); ++j) ^ user.cpp:54:13: warning: unused variable ‘x’ [-Wunused-variable] int n, m, x, s; ^ user.cpp:54:16: warning: unused variable ‘s’ [-Wunused-variable] int n, m, x, s; ^ user.cpp:55:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.in", "r", stdin); ^ user.cpp:56:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.out", "w", stdout); ^ user.cpp:57:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:59:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a[i], &b[i]); ^