[1806] Minimum Number of Operations to Reinitialize a Permutation

嗯～～～好吧～既然題目Hint都說了，可以用暴力解 XD

那就先這樣吧(逃走)

int reinitializePermutation(int n){

int *perm=calloc(n, sizeof(int));

int *arr=calloc(n, sizeof(int));

for (int i=0;i<n;i++)

perm[i]=i;

int count=0;

bool flag=true;

while (flag)

{

count++;

flag=false;

for (int i=0;i<n;i++)

{

int index=-1;

if (i%2==0)

index=i/2;

else if (i%2==1)

index=n/2+(i-1)/2;

arr[i]=perm[index];

if (arr[i]!=i)

flag=true;

}

memcpy(perm, arr, sizeof(int)*n);

}

return count;

}

PS: 雖然回圈裡的index 可以拿掉不用，但感覺在[] 裡面做運算速度好像會變慢捏?!

int reinitializePermutation(int n){

int *perm=calloc(n, sizeof(int));

int *arr=calloc(n, sizeof(int));

for (int i=0;i<n;i++)

perm[i]=i;

int count=0;

bool flag=true;

while (flag)

{

count++;

flag=false;

for (int i=0;i<n;i++)

{

if (i%2==0)

arr[i]=perm[i/2];

else if (i%2==1)

arr[i]=perm[n/2+(i-1)/2];

if (arr[i]!=i)

flag=true;

}

memcpy(perm, arr, sizeof(int)*n);

}

return count;

}