Compilare: main.cpp: In function 'void dfs(int, int)': main.cpp:42:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[x].size(); i++) ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:110:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < fr.size(); i++) { ~~^~~~~~~~~~~ main.cpp:130:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < fr.size(); k++) { ~~^~~~~~~~~~~ main.cpp:87:13: warning: unused variable 'nfr' [-Wunused-variable] int x, y, nfr; ^~~ main.cpp:85:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("tairos.in", "r", stdin); ^ main.cpp:86:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("tairos.out", "w", stdout); ^ main.cpp:89:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n%d", &n, &d); ^ main.cpp:91:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^