Compilare: main.cpp: In function 'int dijkstra(int)': main.cpp:35:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < G[x].size() ; j ++) ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:78:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("lanterna.in" , "r" , stdin); ^ main.cpp:79:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("lanterna.out" , "w" , stdout); ^ main.cpp:81:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d" , &n , &k); ^ main.cpp:83:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &type[i]); ^ main.cpp:84:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &m); ^ main.cpp:87:46: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d" , &x , &y , &z , &t); ^