Descompune_O_Permutare_In__Cicluri

#include <bits/stdc++.h>
#include <stdlib.h>
using namespace std;
typedef void(*cyclefn)(const unsigned int *, size_t);

void permutation_cycles_recursive(const unsigned int *permutation, unsigned int *visited,
        unsigned int start, unsigned int current, unsigned int *path,
        size_t length, cyclefn fun)
{
    visited[current] = 1;
    path[length] = current;
    if (start == current && length > 0) {
        fun(path, length);
    }
    else {
        permutation_cycles_recursive(permutation, visited, start, permutation[current],
                path, length + 1, fun);
    }
}

void permutation_cycles(const unsigned int *permutation, size_t n, cyclefn fun)
{
    unsigned int i;
    unsigned int *visited = new unsigned int[n];
    unsigned int *path = new unsigned int[n];
    if (!(visited && path)) {
        free(visited);
        free(path);
        return;
    }
    for (i = 0; i < n; i++) {
        if (!visited[i]) {
            permutation_cycles_recursive(permutation, visited, i, i, path, 0, fun);
        }
    }
    free(visited);
    free(path);
}

void print(const unsigned int *cycle, size_t length)
{
    if (length > 1) {
        unsigned int i;
        putchar('(');
        for (i = 0; i < length; i++) {
            printf("%u", cycle[i]);
            if (i < length - 1) {
                printf(", ");
            }
        }
        putchar(')');
    }
}

int main(void)
{
    unsigned int permutation[] ={0, 3, 4, 2, 1}; ///alt exemplu  {1, 3, 7, 0, 4, 8, 2, 6, 5};
    const size_t n = sizeof(permutation) / sizeof(permutation[0]);
    permutation_cycles(permutation, n, print);
    putchar('\n');
    return 0;
}