传送门


暴力枚举\(0\)的长度,如果对应的\(1\)的长度也是一个整数就去check是否合法。check使用字符串哈希。

复杂度看起来是\(O(st)\)的,但是因为\(01\)两个数中数量较多的至少有\(\frac{|s|}{2}\)个,那么最多有\(\frac{2|t|}{|s|}\)个可能的答案,而每一次check是\(O(|s|)\)的,所以总复杂度是\(O(|t|)\)的

#include<bits/stdc++.h>
#define ll long long
#define PLL pair < ll , ll >
//This code is written by Itst
using namespace std; inline int read(){
int a = 0;
char c = getchar();
bool f = 0;
while(!isdigit(c) && c != EOF){
if(c == '-')
f = 1;
c = getchar();
}
if(c == EOF)
exit(0);
while(isdigit(c)){
a = (a << 3) + (a << 1) + (c ^ '0');
c = getchar();
}
return f ? -a : a;
} const int seed = 13331 , MOD1 = 1e9 + 7 , MOD2 = 1e9 + 9;
char s1[100010] , s2[1000010];
int L1 , L2 , cnt0 , cnt1 , cnt;
ll Hash[1000010][2] , poww[1000010][2]; void input(){
scanf("%s %s" , s1 + 1 , s2 + 1);
L1 = strlen(s1 + 1);
L2 = strlen(s2 + 1);
} void init(){
for(int i = 1 ; i <= L1 ; ++i)
s1[i] == '0' ? ++cnt0 : ++cnt1;
poww[0][0] = poww[0][1] = 1;
for(int i = 1 ; i <= L2 ; ++i){
Hash[i][0] = (Hash[i - 1][0] * seed + s2[i]) % MOD1;
Hash[i][1] = (Hash[i - 1][1] * seed + s2[i]) % MOD2;
poww[i][0] = poww[i - 1][0] * seed % MOD1;
poww[i][1] = poww[i - 1][1] * seed % MOD2;
}
} inline PLL calcHash(int i , int j){
return PLL((Hash[i + j - 1][0] - Hash[i - 1][0] * poww[j][0] % MOD1 + MOD1) % MOD1 , (Hash[i + j - 1][1] - Hash[i - 1][1] * poww[j][1] % MOD2 + MOD2) % MOD2);
} void work(){
for(int i = 1 ; i * cnt0 < L2 ; ++i)
if(!((L2 - i * cnt0) % cnt1)){
int p = 1 , j = (L2 - i * cnt0) / cnt1;
bool f = 1;
PLL Hash0 = PLL(-1,0) , Hash1 = PLL(-1,0);
for(int k = 1 ; f && k <= L1 ; ++k)
if(s1[k] == '0'){
if(Hash0.first == -1)
Hash0 = calcHash(p , i);
else
if(Hash0 != calcHash(p , i))
f = 0;
p += i;
}
else{
if(Hash1.first == -1)
Hash1 = calcHash(p , j);
else
if(Hash1 != calcHash(p , j))
f = 0;
p += j;
}
cnt += f && (Hash0 != Hash1);
}
} void output(){
cout << cnt;
} int main(){
#ifndef ONLINE_JUDGE
freopen("in" , "r" , stdin);
//freopen("out" , "w" , stdout);
#endif
input();
init();
work();
output();
return 0;
}
05-07 15:29