Compilare: user.cpp: In function ‘std::pair<int, int> Solve(std::vector<int>, std::vector<int>)’: user.cpp:9:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,line=-1,answer=1,forced=-1,found=0; ^ user.cpp: In function ‘int main()’: user.cpp:63:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("entanglement.in","r",stdin); ^ user.cpp:64:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("entanglement.out","w",stdout); ^ user.cpp:66:44: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&requirement,&n,&m,&k); ^ user.cpp:69:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&c[i][j]); ^