Compilare: user.cpp: In function ‘void lee(int, int)’: user.cpp:48:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, x_aa, y_aa; ^ user.cpp: In function ‘void fel(int, int, int)’: user.cpp:66:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, x_aa, y_aa; ^ user.cpp: In function ‘int main()’: user.cpp:23:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("taxa.in","r",stdin); ^ user.cpp:24:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("taxa.out","w",stdout); ^ user.cpp:28:50: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d %d%d %d%d",&n,&m,&x1,&y1,&x2,&y2); ^ user.cpp:30:55: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for( j = 1; j <= m; ++j ) scanf("%d",&v[i][j]); ^