Compilare: user.cpp: In function ‘int main()’: user.cpp:132:43: warning: left operand of comma operator has no effect [-Wunused-value] for(int i = st.lin, j = st.col; i <= dr.lin, j <= dr.col; i += L1 / l1, j++){ ^ user.cpp:137:42: warning: left operand of comma operator has no effect [-Wunused-value] for(int i = dr.lin, j = st.col; i >= st.lin, j <= dr.col; i -= L1 / l1, j++){ ^ user.cpp:145:43: warning: left operand of comma operator has no effect [-Wunused-value] for(int i = st.lin, j = st.col; i <= dr.lin, j <= dr.col; i ++, j += l1 / L1){ ^ user.cpp:150:42: warning: left operand of comma operator has no effect [-Wunused-value] for(int i = dr.lin, j = st.col; i >= st.lin, j <= dr.col; i--, j += l1 / L1){ ^ user.cpp:163:43: warning: left operand of comma operator has no effect [-Wunused-value] for(int i = st.lin, j = st.col; i <= dr.lin, j <= dr.col; i += L2 / l2, j++){ ^ user.cpp:168:42: warning: left operand of comma operator has no effect [-Wunused-value] for(int i = dr.lin, j = st.col; i >= st.lin, j <= dr.col; i -= L2 / l2, j++){ ^ user.cpp:176:43: warning: left operand of comma operator has no effect [-Wunused-value] for(int i = st.lin, j = st.col; i <= dr.lin, j <= dr.col; i ++, j += l2 / L2){ ^ user.cpp:181:42: warning: left operand of comma operator has no effect [-Wunused-value] for(int i = dr.lin, j = st.col; i >= st.lin, j <= dr.col; i--, j += l2 / L2){ ^