Compilare: main.cpp: In function 'void dfs1(int, int)': main.cpp:26:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < a[x].size(); i++) { ~~^~~~~~~~~~~~~ main.cpp: In function 'void dfs2(int, int, int)': main.cpp:38:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < a[x].size(); i++) ~~^~~~~~~~~~~~~ main.cpp:41:41: warning: suggest parentheses around comparison in operand of '|' [-Wparentheses] if (dp[px][1 - cur] == 0 && (px == 1 | dp[px][2] == 1)) { ~~~^~~~ main.cpp:48:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < a[x].size(); i++) { ~~^~~~~~~~~~~~~ main.cpp: In function 'void solve()': main.cpp:62:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < a[1].size(); i++) ~~^~~~~~~~~~~~~