Compilare: main.cpp: In function 'void dfs_down(int, int)': main.cpp:18:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v[nod].size() ; i++){ ~~^~~~~~~~~~~~~~~ main.cpp: In function 'void dfs_upin(int, int)': main.cpp:47:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v[nod].size() ; i++){ ~~^~~~~~~~~~~~~~~ main.cpp:69:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v[nod].size() ; i++){ ~~^~~~~~~~~~~~~~~ main.cpp:42:31: warning: unused variable 'cost_in' [-Wunused-variable] int i , vecin , c1 , c2 , cost_in , cost_out; ^~~~~~~ main.cpp:42:41: warning: unused variable 'cost_out' [-Wunused-variable] int i , vecin , c1 , c2 , cost_in , cost_out; ^~~~~~~~ main.cpp:43:15: warning: unused variable 'sum_in' [-Wunused-variable] long long sum_in , maxi = 0; ^~~~~~ main.cpp:43:24: warning: unused variable 'maxi' [-Wunused-variable] long long sum_in , maxi = 0; ^~~~ main.cpp: In function 'void dfs_upout(int, int)': main.cpp:93:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v[nod].size() ; i++){ ~~^~~~~~~~~~~~~~~ main.cpp:112:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v[tt].size() ; i++){ ~~^~~~~~~~~~~~~~ main.cpp:130:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v[nod].size() ; i++){ ~~^~~~~~~~~~~~~~~ main.cpp: In function 'void solve(int, int)': main.cpp:158:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v[nod].size() ; i++){ ~~^~~~~~~~~~~~~~~ main.cpp:185:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < v[nod].size() ; i++){ ~~^~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:206:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&n); ^ main.cpp:208:44: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d%d%d",&x,&y,&a,&b); ^ main.cpp: In function 'void dfs_upout(int, int)': main.cpp:120:84: warning: 'c_in' may be used uninitialized in this function [-Wmaybe-uninitialized] up_out[nod] = max(up_out[nod] , down_out[vecin] + c1 + down_in[tt] + c_in -