Compilare: main.cpp: In function 'bool bellman()': main.cpp:43:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[nod].size(); i++) ~~^~~~~~~~~~~~~~~ main.cpp: At global scope: main.cpp:68:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] main() ^ main.cpp: In function 'int main()': main.cpp:134:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < v[i].size(); j++) ~~^~~~~~~~~~~~~ main.cpp:143:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < sol.size(); i++) ~~^~~~~~~~~~~~