#ifndef foreach

#define foreach_iter_var(var) var ## _iter
#define foreach(var, val) \
    for (typeof(val.begin()) foreach_iter_var(var) = (val).begin(), \
            _ = (val).begin(); \
            foreach_iter_var(var) != (val).end(); \
            foreach_iter_var(var)++, _ = (val).begin()) \
        for (typeof(*foreach_iter_var(var)) var = *foreach_iter_var(var); \
                _ != (val).end(); \
                _ = (val).end())

#endif