(i<=0 || xbt_matrix_get_as(C,i,j-1,int) >= xbt_matrix_get_as(C,i-1,j,int))) {
diff_build_diff(res,C,da,db,i,j-1);
topush = bprintf("+ %s",xbt_dynar_get_as(db,j,char*));
xbt_dynar_push(res,&topush);
(i<=0 || xbt_matrix_get_as(C,i,j-1,int) >= xbt_matrix_get_as(C,i-1,j,int))) {
diff_build_diff(res,C,da,db,i,j-1);
topush = bprintf("+ %s",xbt_dynar_get_as(db,j,char*));
xbt_dynar_push(res,&topush);