大数模板

#include <stdio.h>
#include <string.h>
#include <math.h>


#define max(a,b) (a)>(b)?(a):(b)
#define min(a,b) (a)<(b)?(a):(b)

const int MAXSIZE = 10000;

struct bign {
    int s[MAXSIZE];
    bign ()    {memset(s, 0, sizeof(s));}
    bign (int number) {*this = number;}
    bign (const char* number) {*this = number;}

    void put();
    bign mul(int d);
    void del();
    void init() { memset(s, 0, sizeof(s)); }

    bign operator =  (char *num);
    bign operator =  (int num);

    bool operator <  (const bign& b) const;
    bool operator >  (const bign& b) const { return b < *this; }
    bool operator <= (const bign& b) const { return !(b < *this); }
    bool operator >= (const bign& b) const { return !(*this < b); }
    bool operator != (const bign& b) const { return b < *this || *this < b;}
    bool operator == (const bign& b) const { return !(b != *this); }

    bign operator + (const bign& c);
    bign operator * (const bign& c);
    bign operator - (const bign& c);
    int  operator / (const bign& c);
    bign operator / (int k);
    bign operator % (const bign &c);
    int  operator % (int k);
    void operator ++ ();
    bool operator -- ();
};

bign bign::operator = (char *num) {
    init();
    s[0] = strlen(num);
    for (int i = 1; i <= s[0]; i++)
        s[i] = num[s[0] - i] - ‘0‘;
    return *this;
}

bign bign::operator = (int num) {
    char str[MAXSIZE];
    sprintf(str, "%d", num);
    return *this = str;
}

bool bign::operator < (const bign& b) const {
    if (s[0] != b.s[0])
        return s[0] < b.s[0];
    for (int i = s[0]; i; i--)
        if (s[i] != b.s[i])
            return s[i] < b.s[i];
        return false;
}

bign bign::operator + (const bign& c) {
    int sum = 0;
    bign ans;
    ans.s[0] = max(s[0], c.s[0]);

    for (int i = 1; i <= ans.s[0]; i++) {
        if (i <= s[0]) sum += s[i];
        if (i <= c.s[0]) sum += c.s[i];
        ans.s[i] = sum % 10;
        sum /= 10;
    }
    return ans;
}

bign bign::operator * (const bign& c) {
    bign ans;
    ans.s[0] = 0;

    for (int i = 1; i <= c.s[0]; i++){
        int g = 0;

        for (int j = 1; j <= s[0]; j++){
            int x = s[j] * c.s[i] + g + ans.s[i + j - 1];
            ans.s[i + j - 1] = x % 10;
            g = x / 10;
        }
        int t = i + s[0] - 1;

        while (g){
            ++t;
            g += ans.s[t];
            ans.s[t] = g % 10;
            g = g / 10;
        }

        ans.s[0] = max(ans.s[0], t);
    }
    ans.del();
    return ans;
}

bign bign::operator - (const bign& c) {
    bign ans = *this;
    int i;
    for (i = 1; i <= c.s[0]; i++) {
        if (ans.s[i] < c.s[i]) {
            ans.s[i] += 10;
            ans.s[i + 1]--;;
        }
        ans.s[i] -= c.s[i];
    }

    for (i = 1; i <= ans.s[0]; i++) {
        if (ans.s[i] < 0) {
            ans.s[i] += 10;
            ans.s[i + 1]--;
        }
    }

    ans.del();
    return ans;
}

int bign::operator / (const bign& c) {
    int ans = 0;
    bign d = *this;
    while (d >= c) {
        d = d - c;
        ans++;
    }
    return ans;
}

bign bign::operator / (int k) {
    bign ans;
    ans.s[0] = s[0];
    int num = 0;
    for (int i = s[0]; i; i--) {
        num = num * 10 + s[i];
        ans.s[i] = num / k;
        num = num % k;
    }
    ans.del();
    return ans;
}

int bign:: operator % (int k){
    int sum = 0;
    for (int i = s[0]; i; i--){
        sum = sum * 10 + s[i];
        sum = sum % k;
    }
    return sum;
}

bign bign::operator % (const bign &c) {
    bign now = *this;
    while (now >= c) {
        now = now - c;
        now.del();
    }
    return now;
}

void bign::operator ++ () {
    s[1]++;
    for (int i = 1; s[i] == 10; i++) {
        s[i] = 0;
        s[i + 1]++;
        s[0] = max(s[0], i + 1);
    }
}

bool bign::operator -- () {
    del();
    if (s[0] == 1 && s[1] == 0) return false;

    int i;
    for (i = 1; s[i] == 0; i++)
        s[i] = 9;
    s[i]--;
    del();
    return true;
}

void bign::put() {
    if (s[0] == 0)
        printf("0");
    else
        for (int i = s[0]; i; i--)
            printf("%d", s[i]);
}

bign bign::mul(int d) {
    s[0] += d;
    int i;
    for (i = s[0]; i > d; i--)
        s[i] = s[i - d];
    for (i = d; i; i--)
        s[i] = 0;
    return *this;
}

void bign::del() {
    while (s[s[0]] == 0) {
        s[0]--;
        if (s[0] == 0) break;
    }
}
int main() {
    return 0;
}