UVA10069 Distinct Subsequences 超级大数 + DP

一万多的代码，看着好乱，有点吓人，JAVA还没学会，不然就很短了

题意是给你一个母串一个子串，问你子串在母串中出现的次数，一个字母可以用多次，但是没找到一个 子串它的元素 下标组合必须不同

比如母串babgbag 

子串bag,

你可以找到 五个，

rabbbit
rabbit

你可以找到三个

总是做算法，不如来个陶冶情操的文章一篇： http://www.sanwen.net/subject/3628849/

数的时候用的是排列组合的方法来数的，DP方程比较简单的，直接for两层找相同的，有点话就加上之前 保存的

dp[i][j] += dp[i-][j-1]

一开始找案例找了半天不是到哪里错，后来看到题目说 保证 答案不超过 10^100，那这个数就太大了 ，只能用大数来做

#include<iostream>
#include<cstdio>
#include<list>
#include<algorithm>
#include<cstring>
#include<string>
#include<queue>
#include<stack>
#include<map>
#include<vector>
#include<cmath>
#include<memory.h>
#include<set>

#define ll long long

#define eps 1e-8

#define inf 0xfffffff

//const ll INF = 1ll<<61;

using namespace std;

//vector<pair<int,int> > G;
//typedef pair<int,int > P;
//vector<pair<int,int> > ::iterator iter;
//
//map<ll,int >mp;
//map<ll,int >::iterator p;

const int N = 10000 + 5;
const int M = 100 + 5;

#define DIGIT 4
#define DEPTH 10000
#define MAX 101
typedef int bignum_t[MAX + 1];

int read(bignum_t a, istream& is = cin){
char buf[MAX*DIGIT + 1], ch;
int i, j;
memset((void*)a, 0, sizeof(bignum_t));
if (!(is >> buf)) return 0;
for (a[0] = strlen(buf), i = a[0] / 2 - 1; i >= 0; i--)
ch = buf[i], buf[i] = buf[a[0] - 1 - i], buf[a[0] - 1 - i] = ch;
for (a[0] = (a[0] + DIGIT - 1) / DIGIT, j = strlen(buf); j<a[0] * DIGIT; buf[j++] = '0');
for (i = 1; i <= a[0]; i++)
for (a[i] = 0, j = 0; j<DIGIT; j++)
a[i] = a[i] * 10 + buf[i*DIGIT - 1 - j] - '0';
for (; !a[a[0]] && a[0]>1; a[0]--);
return 1;
}

void write(const bignum_t a, ostream& os = cout){
int i, j;
for (os << a[i = a[0]], i--; i; i--)
for (j = DEPTH / 10; j; j /= 10)
os << a[i] / j % 10;
}

int comp(const bignum_t a, const bignum_t b){
int i;
if (a[0] != b[0])
return a[0] - b[0];
for (i = a[0]; i; i--)
if (a[i] != b[i])
return a[i] - b[i];
return 0;
}

int comp(const bignum_t a, const int b){
int c[12] = { 1 };
for (c[1] = b; c[c[0]] >= DEPTH; c[c[0] + 1] = c[c[0]] / DEPTH, c[c[0]] %= DEPTH, c[0]++);
return comp(a, c);
}

int comp(const bignum_t a, const int c, const int d, const bignum_t b){
int i, t = 0, O = -DEPTH * 2;
if (b[0] - a[0]<d&&c)
return 1;
for (i = b[0]; i>d; i--){
t = t*DEPTH + a[i - d] * c - b[i];
if (t>0) return 1;
if (t<O) return 0;
}
for (i = d; i; i--){
t = t*DEPTH - b[i];
if (t>0) return 1;
if (t<O) return 0;
}
return t>0;
}

void add(bignum_t a, const bignum_t b){
int i;
for (i = 1; i <= b[0]; i++)
if ((a[i] += b[i]) >= DEPTH)
a[i] -= DEPTH, a[i + 1]++;
if (b[0] >= a[0])
a[0] = b[0];
else
for (; a[i] >= DEPTH&&i<a[0]; a[i] -= DEPTH, i++, a[i]++);
a[0] += (a[a[0] + 1]>0);
}

void add(bignum_t a, const int b){
int i = 1;
for (a[1] += b; a[i] >= DEPTH&&i<a[0]; a[i + 1] += a[i] / DEPTH, a[i] %= DEPTH, i++);
for (; a[a[0]] >= DEPTH; a[a[0] + 1] = a[a[0]] / DEPTH, a[a[0]] %= DEPTH, a[0]++);
}

void sub(bignum_t a, const bignum_t b){
int i;
for (i = 1; i <= b[0]; i++)
if ((a[i] -= b[i])<0)
a[i + 1]--, a[i] += DEPTH;
for (; a[i]<0; a[i] += DEPTH, i++, a[i]--);
for (; !a[a[0]] && a[0]>1; a[0]--);
}

void sub(bignum_t a, const int b){
int i = 1;
for (a[1] -= b; a[i]<0; a[i + 1] += (a[i] - DEPTH + 1) / DEPTH, a[i] -= (a[i] - DEPTH + 1) / DEPTH*DEPTH, i++);
for (; !a[a[0]] && a[0]>1; a[0]--);
}

void sub(bignum_t a, const bignum_t b, const int c, const int d){
int i, O = b[0] + d;
for (i = 1 + d; i <= O; i++)
if ((a[i] -= b[i - d] * c)<0)
a[i + 1] += (a[i] - DEPTH + 1) / DEPTH, a[i] -= (a[i] - DEPTH + 1) / DEPTH*DEPTH;
for (; a[i]<0; a[i + 1] += (a[i] - DEPTH + 1) / DEPTH, a[i] -= (a[i] - DEPTH + 1) / DEPTH*DEPTH, i++);
for (; !a[a[0]] && a[0]>1; a[0]--);
}

void mul(bignum_t c, const bignum_t a, const bignum_t b){
int i, j;
memset((void*)c, 0, sizeof(bignum_t));
for (c[0] = a[0] + b[0] - 1, i = 1; i <= a[0]; i++)
for (j = 1; j <= b[0]; j++)
if ((c[i + j - 1] += a[i] * b[j]) >= DEPTH)
c[i + j] += c[i + j - 1] / DEPTH, c[i + j - 1] %= DEPTH;
for (c[0] += (c[c[0] + 1]>0); !c[c[0]] && c[0]>1; c[0]--);
}

void mul(bignum_t a, const int b){
int i;
for (a[1] *= b, i = 2; i <= a[0]; i++){
a[i] *= b;
if (a[i - 1] >= DEPTH)
a[i] += a[i - 1] / DEPTH, a[i - 1] %= DEPTH;
}
for (; a[a[0]] >= DEPTH; a[a[0] + 1] = a[a[0]] / DEPTH, a[a[0]] %= DEPTH, a[0]++);
for (; !a[a[0]] && a[0]>1; a[0]--);
}

void mul(bignum_t b, const bignum_t a, const int c, const int d){
int i;
memset((void*)b, 0, sizeof(bignum_t));
for (b[0] = a[0] + d, i = d + 1; i <= b[0]; i++)
if ((b[i] += a[i - d] * c) >= DEPTH)
b[i + 1] += b[i] / DEPTH, b[i] %= DEPTH;
for (; b[b[0] + 1]; b[0]++, b[b[0] + 1] = b[b[0]] / DEPTH, b[b[0]] %= DEPTH);
for (; !b[b[0]] && b[0]>1; b[0]--);
}

void div(bignum_t c, bignum_t a, const bignum_t b){
int h, l, m, i;
memset((void*)c, 0, sizeof(bignum_t));
c[0] = (b[0]<a[0] + 1) ? (a[0] - b[0] + 2) : 1;
for (i = c[0]; i; sub(a, b, c[i] = m, i - 1), i--)
for (h = DEPTH - 1, l = 0, m = (h + l + 1) >> 1; h>l; m = (h + l + 1) >> 1)
if (comp(b, m, i - 1, a)) h = m - 1;
else l = m;
for (; !c[c[0]] && c[0]>1; c[0]--);
c[0] = c[0]>1 ? c[0] : 1;
}

void div(bignum_t a, const int b, int& c){
int i;
for (c = 0, i = a[0]; i; c = c*DEPTH + a[i], a[i] = c / b, c %= b, i--);
for (; !a[a[0]] && a[0]>1; a[0]--);
}

void sqrt(bignum_t b, bignum_t a){
int h, l, m, i;
memset((void*)b, 0, sizeof(bignum_t));
for (i = b[0] = (a[0] + 1) >> 1; i; sub(a, b, m, i - 1), b[i] += m, i--)
for (h = DEPTH - 1, l = 0, b[i] = m = (h + l + 1) >> 1; h>l; b[i] = m = (h + l + 1) >> 1)
if (comp(b, m, i - 1, a)) h = m - 1;
else l = m;
for (; !b[b[0]] && b[0]>1; b[0]--);
for (i = 1; i <= b[0]; b[i++] >>= 1);
}

int length(const bignum_t a){
int t, ret;
for (ret = (a[0] - 1)*DIGIT, t = a[a[0]]; t; t /= 10, ret++);
return ret>0 ? ret : 1;
}

int digit(const bignum_t a, const int b){
int i, ret;
for (ret = a[(b - 1) / DIGIT + 1], i = (b - 1) % DIGIT; i; ret /= 10, i--);
return ret % 10;
}

int zeronum(const bignum_t a){
int ret, t;
for (ret = 0; !a[ret + 1]; ret++);
for (t = a[ret + 1], ret *= DIGIT; !(t % 10); t /= 10, ret++);
return ret;
}

void comp(int* a, const int l, const int h, const int d){
int i, j, t;
for (i = l; i <= h; i++)
for (t = i, j = 2; t>1; j++)
while (!(t%j))
a[j] += d, t /= j;
}

void convert(int* a, const int h, bignum_t b){
int i, j, t = 1;
memset(b, 0, sizeof(bignum_t));
for (b[0] = b[1] = 1, i = 2; i <= h; i++)
if (a[i])
for (j = a[i]; j; t *= i, j--)
if (t*i>DEPTH)
mul(b, t), t = 1;
mul(b, t);
}

void combination(bignum_t a, int m, int n){
int* t = new int[m + 1];
memset((void*)t, 0, sizeof(int)*(m + 1));
comp(t, n + 1, m, 1);
comp(t, 2, m - n, -1);
convert(t, m, a);
delete[]t;
}

void permutation(bignum_t a, int m, int n){
int i, t = 1;
memset(a, 0, sizeof(bignum_t));
a[0] = a[1] = 1;
for (i = m - n + 1; i <= m; t *= i++)
if (t*i>DEPTH)
mul(a, t), t = 1;
mul(a, t);
}

#define SGN(x) ((x)>0?1:((x)<0?-1:0))
#define ABS(x) ((x)>0?(x):-(x))

int read(bignum_t a, int &sgn, istream& is = cin){
char str[MAX*DIGIT + 2], ch, *buf;
int i, j;
memset((void*)a, 0, sizeof(bignum_t));
if (!(is >> str)) return 0;
buf = str, sgn = 1;
if (*buf == '-') sgn = -1, buf++;
for (a[0] = strlen(buf), i = a[0] / 2 - 1; i >= 0; i--)
ch = buf[i], buf[i] = buf[a[0] - 1 - i], buf[a[0] - 1 - i] = ch;
for (a[0] = (a[0] + DIGIT - 1) / DIGIT, j = strlen(buf); j<a[0] * DIGIT; buf[j++] = '0');
for (i = 1; i <= a[0]; i++)
for (a[i] = 0, j = 0; j<DIGIT; j++)
a[i] = a[i] * 10 + buf[i*DIGIT - 1 - j] - '0';
for (; !a[a[0]] && a[0]>1; a[0]--);
if (a[0] == 1 && !a[1]) sgn = 0;
return 1;
}

struct bignum{
bignum_t num;
int sgn;
public:
inline bignum(){ memset(num, 0, sizeof(bignum_t)); num[0] = 1; sgn = 0; }
inline int operator!(){ return num[0] == 1 && !num[1]; }
inline bignum& operator=(const bignum& a){ memcpy(num, a.num, sizeof(bignum_t)); sgn = a.sgn; return *this; }
inline bignum& operator=(const int a){ memset(num, 0, sizeof(bignum_t)); num[0] = 1; sgn = SGN(a); add(num, sgn*a); return *this; };
inline bignum& operator+=(const bignum& a){
if (sgn == a.sgn)add(num, a.num); else if (sgn&&a.sgn){
int ret = comp(num, a.num); if (ret>0)sub(num, a.num); else if (ret<0){
bignum_t t;
memcpy(t, num, sizeof(bignum_t)); memcpy(num, a.num, sizeof(bignum_t)); sub(num, t); sgn = a.sgn;
}
else memset(num, 0, sizeof(bignum_t)), num[0] = 1, sgn = 0;
}
else if (!sgn)memcpy(num, a.num, sizeof(bignum_t)), sgn = a.sgn; return *this;
}
inline bignum& operator+=(const int a){
if (sgn*a>0)add(num, ABS(a)); else if (sgn&&a){
int ret = comp(num, ABS(a)); if (ret>0)sub(num, ABS(a)); else if (ret<0){
bignum_t t;
memcpy(t, num, sizeof(bignum_t)); memset(num, 0, sizeof(bignum_t)); num[0] = 1; add(num, ABS(a)); sgn = -sgn; sub(num, t);
}
else memset(num, 0, sizeof(bignum_t)), num[0] = 1, sgn = 0;
}
else if (!sgn)sgn = SGN(a), add(num, ABS(a)); return *this;
}
inline bignum operator+(const bignum& a){ bignum ret; memcpy(ret.num, num, sizeof(bignum_t)); ret.sgn = sgn; ret += a; return ret; }
inline bignum operator+(const int a){ bignum ret; memcpy(ret.num, num, sizeof(bignum_t)); ret.sgn = sgn; ret += a; return ret; }
inline bignum& operator-=(const bignum& a){
if (sgn*a.sgn<0)add(num, a.num); else if (sgn&&a.sgn){
int ret = comp(num, a.num); if (ret>0)sub(num, a.num); else if (ret<0){
bignum_t t;
memcpy(t, num, sizeof(bignum_t)); memcpy(num, a.num, sizeof(bignum_t)); sub(num, t); sgn = -sgn;
}
else memset(num, 0, sizeof(bignum_t)), num[0] = 1, sgn = 0;
}
else if (!sgn)add(num, a.num), sgn = -a.sgn; return *this;
}
inline bignum& operator-=(const int a){
if (sgn*a<0)add(num, ABS(a)); else if (sgn&&a){
int ret = comp(num, ABS(a)); if (ret>0)sub(num, ABS(a)); else if (ret<0){
bignum_t t;
memcpy(t, num, sizeof(bignum_t)); memset(num, 0, sizeof(bignum_t)); num[0] = 1; add(num, ABS(a)); sub(num, t); sgn = -sgn;
}
else memset(num, 0, sizeof(bignum_t)), num[0] = 1, sgn = 0;
}
else if (!sgn)sgn = -SGN(a), add(num, ABS(a)); return *this;
}
inline bignum operator-(const bignum& a){ bignum ret; memcpy(ret.num, num, sizeof(bignum_t)); ret.sgn = sgn; ret -= a; return ret; }
inline bignum operator-(const int a){ bignum ret; memcpy(ret.num, num, sizeof(bignum_t)); ret.sgn = sgn; ret -= a; return ret; }
inline bignum& operator*=(const bignum& a){ bignum_t t; mul(t, num, a.num); memcpy(num, t, sizeof(bignum_t)); sgn *= a.sgn; return *this; }
inline bignum& operator*=(const int a){ mul(num, ABS(a)); sgn *= SGN(a); return *this; }
inline bignum operator*(const bignum& a){ bignum ret; mul(ret.num, num, a.num); ret.sgn = sgn*a.sgn; return ret; }
inline bignum operator*(const int a){ bignum ret; memcpy(ret.num, num, sizeof(bignum_t)); mul(ret.num, ABS(a)); ret.sgn = sgn*SGN(a); return ret; }
inline bignum& operator/=(const bignum& a){ bignum_t t; div(t, num, a.num); memcpy(num, t, sizeof(bignum_t)); sgn = (num[0] == 1 && !num[1]) ? 0 : sgn*a.sgn; return *this; }
inline bignum& operator/=(const int a){ int t; div(num, ABS(a), t); sgn = (num[0] == 1 && !num[1]) ? 0 : sgn*SGN(a); return *this; }
inline bignum operator/(const bignum& a){ bignum ret; bignum_t t; memcpy(t, num, sizeof(bignum_t)); div(ret.num, t, a.num); ret.sgn = (ret.num[0] == 1 && !ret.num[1]) ? 0 : sgn*a.sgn; return ret; }
inline bignum operator/(const int a){ bignum ret; int t; memcpy(ret.num, num, sizeof(bignum_t)); div(ret.num, ABS(a), t); ret.sgn = (ret.num[0] == 1 && !ret.num[1]) ? 0 : sgn*SGN(a); return ret; }
inline bignum& operator%=(const bignum& a){ bignum_t t; div(t, num, a.num); if (num[0] == 1 && !num[1])sgn = 0; return *this; }
inline int operator%=(const int a){ int t; div(num, ABS(a), t); memset(num, 0, sizeof(bignum_t)); num[0] = 1; add(num, t); return t; }
inline bignum operator%(const bignum& a){ bignum ret; bignum_t t; memcpy(ret.num, num, sizeof(bignum_t)); div(t, ret.num, a.num); ret.sgn = (ret.num[0] == 1 && !ret.num[1]) ? 0 : sgn; return ret; }
inline int operator%(const int a){ bignum ret; int t; memcpy(ret.num, num, sizeof(bignum_t)); div(ret.num, ABS(a), t); memset(ret.num, 0, sizeof(bignum_t)); ret.num[0] = 1; add(ret.num, t); return t; }
inline bignum& operator++(){ *this += 1; return *this; }
inline bignum& operator--(){ *this -= 1; return *this; };
inline int operator>(const bignum& a){ return sgn>0 ? (a.sgn>0 ? comp(num, a.num)>0:1) : (sgn<0 ? (a.sgn<0 ? comp(num, a.num)<0 : 0) : a.sgn<0); }
inline int operator>(const int a){ return sgn>0 ? (a>0 ? comp(num, a)>0:1) : (sgn<0 ? (a<0 ? comp(num, -a)<0 : 0) : a<0); }
inline int operator>=(const bignum& a){ return sgn>0 ? (a.sgn>0 ? comp(num, a.num) >= 0 : 1) : (sgn<0 ? (a.sgn<0 ? comp(num, a.num) <= 0 : 0) : a.sgn <= 0); }
inline int operator>=(const int a){ return sgn>0 ? (a>0 ? comp(num, a) >= 0 : 1) : (sgn<0 ? (a<0 ? comp(num, -a) <= 0 : 0) : a <= 0); }
inline int operator<(const bignum& a){ return sgn<0 ? (a.sgn<0 ? comp(num, a.num)>0:1) : (sgn>0 ? (a.sgn>0 ? comp(num, a.num)<0 : 0) : a.sgn>0); }
inline int operator<(const int a){ return sgn<0 ? (a<0 ? comp(num, -a)>0:1) : (sgn>0 ? (a>0 ? comp(num, a)<0 : 0) : a>0); }
inline int operator<=(const bignum& a){ return sgn<0 ? (a.sgn<0 ? comp(num, a.num) >= 0 : 1) : (sgn>0 ? (a.sgn>0 ? comp(num, a.num) <= 0 : 0) : a.sgn >= 0); }
inline int operator<=(const int a){ return sgn<0 ? (a<0 ? comp(num, -a) >= 0 : 1) : (sgn>0 ? (a>0 ? comp(num, a) <= 0 : 0) : a >= 0); }
inline int operator==(const bignum& a){ return (sgn == a.sgn) ? !comp(num, a.num) : 0; }
inline int operator==(const int a){ return (sgn*a >= 0) ? !comp(num, ABS(a)) : 0; }
inline int operator!=(const bignum& a){ return (sgn == a.sgn) ? comp(num, a.num) : 1; }
inline int operator!=(const int a){ return (sgn*a >= 0) ? comp(num, ABS(a)) : 1; }
inline int operator[](const int a){ return digit(num, a); }
friend inline istream& operator>>(istream& is, bignum& a){ read(a.num, a.sgn, is); return is; }
friend inline ostream& operator<<(ostream& os, const bignum& a){ if (a.sgn<0)os << '-'; write(a.num, os); return os; }
friend inline bignum sqrt(const bignum& a){ bignum ret; bignum_t t; memcpy(t, a.num, sizeof(bignum_t)); sqrt(ret.num, t); ret.sgn = ret.num[0] != 1 || ret.num[1]; return ret; }
friend inline bignum sqrt(const bignum& a, bignum& b){ bignum ret; memcpy(b.num, a.num, sizeof(bignum_t)); sqrt(ret.num, b.num); ret.sgn = ret.num[0] != 1 || ret.num[1]; b.sgn = b.num[0] != 1 || ret.num[1]; return ret; }
inline int length(){ return ::length(num); }
inline int zeronum(){ return ::zeronum(num); }
inline bignum C(const int m, const int n){ combination(num, m, n); sgn = 1; return *this; }
inline bignum P(const int m, const int n){ permutation(num, m, n); sgn = 1; return *this; }
};
/**********************************************/

bignum dp
[M];

char a
, b[M];

int n,m;

void clear() {
for (int i = 0; i <= n; ++i) dp[i][0] = 1;
}

int main() {
int t;
cin>>t;
while (t--) {
scanf("%s%s", a + 1, b + 1);
a[0] = b[0] = '&';
n = strlen(a) - 1;
m = strlen(b) - 1;
clear();
for (int i=1; i<=n;++i) {
for (int j=1; j<=m;++j) {
dp[i][j] = dp[i - 1][j];
if (a[i] == b[j])
dp[i][j] += dp[i - 1][j - 1];
}
}
cout<<dp
[m]<<endl;
}
return EXIT_SUCCESS;
}