Poj 2406--Power Strings(KMP)

#include <cstdio>
#include <cstring>
#include <iostream>
using namespace std;
char str[1000010]; int len, NeXt[1000010];
void GetP()
{
    int i = 0, j = -1;
    NeXt[i] = j;
    while(i < len)
    {
        if(j == -1 || str[i] == str[j])
        {
            i++; j++;
            if(str[i] != str[j])
                NeXt[i] = j;
            else
                NeXt[i] = NeXt[j];
        }
        else
            j = NeXt[j];
    }
        
} 
int main()
{
    while(gets(str), str[0] != ‘.‘)
    {
        
        len = strlen(str);
        GetP();
        if(len%(len-NeXt[len])==0)
            printf("%d\n", len/(len-NeXt[len]));
        else
            printf("1\n");
    }
    return 0;    
}