Compilare: user.cpp: In function ‘int main()’: user.cpp:104:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < Sol.size() ; ++i){ ~~^~~~~~~~~~~~ user.cpp:106:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i + 1 < Sol.size()) Last = -cost[Sol[i]][Sol[i + 1]]; ~~~~~~^~~~~~~~~~~~ user.cpp:45:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("adn.in", "r", stdin); ^ user.cpp:46:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("adn.out", "w", stdout); ^ user.cpp:47:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:49:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", s[i] + 1); ^