Compilare: main.cpp: In function 'int main()': main.cpp:67:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(sol.size()<k) ~~~~~~~~~~^~ main.cpp:73:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(sol.size()==k) ~~~~~~~~~~^~~ main.cpp:41:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("karb.in", "r", stdin); ^ main.cpp:42:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("karb.out", "w", stdout); ^ main.cpp:44:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &n, &m, &k); ^ main.cpp:49:44: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &x[i], &y[i], &c); ^