Compilare: main.cpp: In function 'void bellmanford()': main.cpp:39:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<arcs[current_node].size(); ++i) { ~^~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'bool dijkstra()': main.cpp:71:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<arcs[current_node].size(); ++i) ~^~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:10:19: warning: suggest parentheses around '-' inside '<<' [-Wparentheses] #define INF 1<<31 - 1 ~~~^~~ main.cpp:89:14: note: in expansion of macro 'INF' current_d = INF; ^~~ main.cpp: In function 'int main()': main.cpp:106:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.in", "r", stdin); ^ main.cpp:107:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.out", "w", stdout); ^ main.cpp:110:43: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &n, &m, &source, &dest); ^ main.cpp:115:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &a, &b, &c, &e); ^