Compilare: user.cpp: In function ‘int main()’: user.cpp:36:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0; j < t[st[i]].size(); j++) ^ user.cpp:47:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0; j < v[st[i]].size(); j++) ^ user.cpp:17:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pawns.in", "r", stdin); ^ user.cpp:18:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pawns.out", "w", stdout); ^ user.cpp:19:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:22:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^ user.cpp:57:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a); ^ user.cpp:63:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &b); ^