sdut 1465 公共因子
http://acm.sdut.edu.cn/sdutoj/problem.php?action=showproblem&problemid=1465
题意：中文.....
思路：
1：暴力枚举两个字符串长度的最大公倍数的因子，作为因子的长度，然后从s1中去出来，做比较，才开始手搓打错了一个地方导致一直tle.
2：同样是枚举两个字符串长度的最大公倍数的因子，作为因子的长度，然后从s1中去出来作比较，这里可以用kmp做，之际一路比较下去。
//#pragma comment(linker,"/STACK:327680000,327680000")
#include <iostream>
#include <cstdio>
#include <cmath>
#include <vector>
#include <cstring>
#include <algorithm>
#include <string>
#include <set>
#include <functional>
#include <numeric>
#include <sstream>
#include <stack>
#include <map>
#include <queue>
#define CL(arr, val) memset(arr, val, sizeof(arr))
#define ll long long
#define inf 0x7f7f7f7f
#define lc l,m,rt<<1
#define rc m + 1,r,rt<<1|1
#define pi acos(-1.0)
#define ll long long
#define L(x) (x) << 1
#define R(x) (x) << 1 | 1
#define MID(l, r) (l + r) >> 1
#define Min(x, y) (x) < (y) ? (x) : (y)
#define Max(x, y) (x) < (y) ? (y) : (x)
#define E(x) (1 << (x))
#define iabs(x) (x) < 0 ? -(x) : (x)
#define OUT(x) printf("%I64d\n", x)
#define lowbit(x) (x)&(-x)
#define Read() freopen("din.txt", "r", stdin)
#define Write() freopen("dout.txt", "w", stdout);
#define N 100007
using namespace std;
char s1[N],s2[N];
char tmp[N],t[N];
int n,m,nm;
int gcd(int i,int j)
{
if (j == 0) return i;
return gcd(j,i%j);
}
bool isNotOk(char *ts,char *tp,int len)
{
int i;
for (i = 0; i < len; ++i)
{
if (ts[i] != tp[i]) return true;
}
return false;
}
int main()
{
//Read();
int cnt,i,j,s;
while (~scanf("%s%s",s1,s2))
{
n = strlen(s1);
m = strlen(s2);
cnt = 0;
nm = gcd(n,m);
for (i = 1; i <= nm; ++i)
{
bool flag = false;
if (nm % i == 0)
{
for (j = 0; j < i; ++j)
tmp[j] = s1[j];
tmp[j] = '\0';
for (j = i; j <= n - i; j += i) //这里是j+=i,手贱写成++了一直tle后来改过就A了
{
int pos = 0;
for (s = j; s < j + i; ++s)
{
t[pos++] = s1[s];
}
t[pos] = '\0';
if (isNotOk(tmp,t,i))
{
flag = true;
break;
}
}
if (flag) continue;
//printf("*************************************\n");
for (j = 0; j <= m - i; j += i)
{
int pos = 0;
for (s = j; s < j + i; ++s)
{
t[pos++] = s2[s];
}
t[pos] = '\0';
if (isNotOk(tmp,t,i))
{
flag = true;
break;
}
}
if (flag) continue;
cnt++;
}
}
printf("%d\n",cnt);
}
return 0;
}
KMP版本：
//#pragma comment(linker,"/STACK:327680000,327680000")
#include <iostream>
#include <cstdio>
#include <cmath>
#include <vector>
#include <cstring>
#include <algorithm>
#include <string>
#include <set>
#include <functional>
#include <numeric>
#include <sstream>
#include <stack>
#include <map>
#include <queue>
#define CL(arr, val) memset(arr, val, sizeof(arr))
#define ll long long
#define inf 0x7f7f7f7f
#define lc l,m,rt<<1
#define rc m + 1,r,rt<<1|1
#define pi acos(-1.0)
#define ll long long
#define L(x) (x) << 1
#define R(x) (x) << 1 | 1
#define MID(l, r) (l + r) >> 1
#define Min(x, y) (x) < (y) ? (x) : (y)
#define Max(x, y) (x) < (y) ? (y) : (x)
#define E(x) (1 << (x))
#define iabs(x) (x) < 0 ? -(x) : (x)
#define OUT(x) printf("%I64d\n", x)
#define lowbit(x) (x)&(-x)
#define Read() freopen("din.txt", "r", stdin)
#define Write() freopen("dout.txt", "w", stdout);
#define N 100007
using namespace std;
char s1[N],s2[N];
char tmp[N],t[N];
int next1[N],next2[N];
int n,m,nm,cnt;
int gcd(int i,int j)
{
if (j == 0) return i;
return gcd(j,i%j);
}
void getNext(char *s,int mk)
{
int i,j;
j = -1;
int len = strlen(s);
if (mk == 1) next1[0] = -1;
else next2[0] = -1;
for (i = 1; i < len; ++i)
{
while (j > -1 && s[j + 1] != s[i])
{
if (mk == 1) j = next1[j];
else j = next2[j];
}
if (s[j + 1] == s[i]) ++j;
if (mk == 1) next1[i] = j;
else next2[i] = j;
}
}
int kmp(char *ts1,char *ts2,int mk)
{
int len1 = strlen(ts1);
int len2 = strlen(ts2);
int i,j;
j = -1;
int ans = 0;
for (i = 0; i < len2; ++i)
{
while (j > -1 && ts1[j + 1] != ts2[i])
{
if (mk == 1) j = next1[j];
else j = next2[j];
}
if (ts1[j + 1] == ts2[i]) ++j;
if (j == len1 - 1)
{
ans++;
j = -1; //这里继续往下比较
}
}
return ans;
}
int main()
{
// Read();
int i,j;
while (~scanf("%s%s",s1,s2))
{
n = strlen(s1);
m = strlen(s2);
nm = gcd(n,m);
// printf("%d\n",nm);
getNext(s1,1);
getNext(s2,2);
cnt = 0;
int ans;
for (i = 1; i <= nm; ++i)
{
if (nm % i == 0)
{
//printf(">>>%d\n",i);
for (j = 0; j < i; ++j)
tmp[j] = s1[j];
tmp[j] = '\0';
// if (n %i != 0 || m % i != 0)
// printf("CUOLE、\n");
ans = kmp(tmp,s1,1);
//printf("1>>%d %d\n",ans,n/i);
if (ans != n/i) continue;
ans = kmp(tmp,s2,2);
// printf("2>>%d %d\n\n",ans,m/i);
if (ans != m/i) continue;
cnt++;
}
}
printf("%d\n",cnt);
}
return 0;
}