Compilare: main.cpp: In function 'int main()': main.cpp:59:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < cord[i].size(); ++j) ~~^~~~~~~~~~~~~~~~ main.cpp:26:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("trampoline.in", "r", stdin); ^ main.cpp:27:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("trampoline.out", "w", stdout); ^ main.cpp:30:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &r, &c, &n); ^ main.cpp:35:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ main.cpp:71:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &q); ^