Compilare: main.cpp: In function 'long double dijkstra()': main.cpp:53:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[node].size(); ++i){ ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:102:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[node].size(); ++i){ ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'void cit(int&)': main.cpp:13:50: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, sizeof(char), DIM, stdin); ^ main.cpp:20:50: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, sizeof(char), DIM, stdin); ^ main.cpp: In function 'int main()': main.cpp:63:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cameras.in","r",stdin); ^ main.cpp:64:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cameras.out","w",stdout); ^