Compilare: main.cpp: In function 'int main()': main.cpp:25:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(v[x].size() < k) ~~~~~~~~~~~~^~~ main.cpp:34:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < v[i].size() ; j ++) ~~^~~~~~~~~~~~~ main.cpp:10:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ausoara.in", "r", stdin); ^ main.cpp:11:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ausoara.out", "w", stdout); ^ main.cpp:13:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:16:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &m); ^ main.cpp:21:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &x); ^