Compilare: user.cpp: In function ‘int main()’: user.cpp:89:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int it = 0; it < v[x].size(); ++it) ^ user.cpp:72:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("djikstra.in","r",stdin); ^ user.cpp:73:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("djikstra.out","w",stdout); ^ user.cpp:74:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:77:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&c); ^