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    /* vim: set tabstop=4 expandtab shiftwidth=4 softtabstop=4: */
    
    /*
     * Copyright 2015 University of Piemonte Orientale, Computer Science Institute
     *
     * This file is part of UPOalglib.
     *
     * UPOalglib is free software: you can redistribute it and/or modify
     * it under the terms of the GNU General Public License as published by
     * the Free Software Foundation, either version 3 of the License, or
     * (at your option) any later version.
     *
     * UPOalglib is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     * GNU General Public License for more details.
     *
     * You should have received a copy of the GNU General Public License
     * along with UPOalglib.  If not, see <http://www.gnu.org/licenses/>.
     */
    
    #include <assert.h>
    #include <stdlib.h>
    #include <upo/random.h>
    #include <upo/utility.h>
    
    
    double upo_random_uniform_real(double lo, double hi)
    {
        return lo + rand()/(RAND_MAX+1.0)*(hi-lo);
    }
    
    int upo_random_uniform_int(int lo, int hi)
    {
        return lo + rand()/(RAND_MAX+1.0)*(hi-lo);
    }
    
    void upo_random_shuffle(void *base, size_t n, size_t size)
    {
        char *ptr = base;
        size_t i;
    
        assert( base != NULL );
    
        for (i = 0; i < n; ++i)
        {   
            size_t r = upo_random_uniform_int(i, n-i);
            if (i != r)
            {
                upo_swap(ptr+i*size, ptr+r*size, size);
            }
        }
    }
    
    char* upo_random_string(char *s, size_t n)
    {
        size_t i = 0;
    
        for (; i < n; ++i)
        {
            s[i] = upo_random_uniform_int(' ', '~');
        }
        s[n] = '\0';
    
        return s;
    }