高精度类－有 + － * / < 还有 开方 等运算

#include<cstdio>#include<cstdlib>#include<cstring>#include<algorithm>using namespace std;const int MOD = 10000;const int BigNumSize = -1;struct BigNum{ int num[BigNumSize]; int l; BigNum MoveZero(); BigNum(int x); BigNum(char * ss); bool operator < (const BigNum & o) const; BigNum operator + (const BigNum & o) const; BigNum operator - () const; BigNum operator - (const BigNum & o) const; BigNum operator * (const BigNum & o) const; BigNum operator * (const int n) const; BigNum operator / (const BigNum & o) const; //BigNum operator / (const int n) const; BigNum sqrt() const; void Print(char * s);};BigNum BigNum::MoveZero(){while (l > 1 && num[l - 1] == 0){l--;}return *this;}BigNum::BigNum(int x = 0){ l = 0; memset(num, 0, sizeof(num)); do { num[l++] = x % MOD; x /= MOD; } while (x);}BigNum::BigNum(char * ss){/* //deal with the negative if (ss[0] == '-'){*this = -BigNum(ss + 1);return;}*/ memset(num, 0, sizeof(num)); int len = strlen(ss); char s[10] = {0}; for (l = 0; len > 4; len -= 4) { strncpy(s, ss + len - 4, 4); num[l++] = atoi(s); } memset(s, 0, sizeof(s)); strncpy(s, ss, len); num[l++] = atoi(s);MoveZero(); return;}bool BigNum:: operator < (const BigNum & o) const{if (l != o.l){return l < o.l;}else {int i = l - 1;while (num[i] == o.num[i]){i--;}return i >= 0 && num[i] < o.num[i];}}BigNum BigNum:: operator + (const BigNum & o) const{/*// deal with the negative if (num[l - 1] < 0 && o.num[o.l - 1] < 0){return - ((-*this) + (-o));}else if (num[l - 1] < 0){return o - (-*this);}else if (o.num[o.l - 1] < 0){return *this - (-o);}*/ int i; BigNum sum; int carry = 0; for (i = 0; i < l || i < o.l; i++) { carry += num[i] + o.num[i]; sum.num[i] = carry % MOD; carry /= MOD; } while (carry) { sum.num[i++] = carry % MOD; carry /= MOD; } sum.l = i; return sum.MoveZero();}BigNum BigNum:: operator - () const{BigNum tmp = *this;tmp.num[l - 1] = -tmp.num[l - 1];return tmp;}BigNum BigNum:: operator - (const BigNum & o) const{int i;int carry = 0;BigNum Dec;if (!((*this) < o)){for (i = 0; i < l; i++){carry += num[i] - o.num[i] + MOD;Dec.num[i] = carry % MOD;carry /= MOD;carry--;}Dec.l = l;return Dec.MoveZero();}else {return -(o - (* this));}}BigNum BigNum:: operator * (const BigNum & o) const{/*// deal with the negative if (num[l - 1] < 0 && o.num[o.l - 1] < 0){return (-*this) * (-o);}else if (num[l - 1] < 0){return -(o * (-*this));}else if (o.num[o.l - 1] < 0){return -(*this * (-o));}*/if (l > o.l){return o * (* this);} int i; int j; BigNum Mul; int carry; for (i = 0; i < l; i++) {if (num[i] == 0){continue;} carry = 0; Mul.l = i; for (j = 0; j < o.l; j++) { carry += num[i] * o.num[j] + Mul.num[Mul.l]; Mul.num[Mul.l++] = carry % MOD; carry /= MOD; } while (carry) { carry += Mul.num[Mul.l]; Mul.num[Mul.l++] = carry % MOD; carry /= MOD; } } return Mul.MoveZero();}BigNum BigNum:: operator * (const int n) const {BigNum ret;if (0 == n){return ret;}int cry = 0;int i;for (i = 0; i < l; i++){cry += num[i] * n;ret.num[i] = cry % MOD;cry /= MOD;}while (cry){ret.num[i++] = cry % MOD;cry /= MOD;}ret.l = i;return ret.MoveZero();}BigNum BigNum:: operator / (const BigNum &o) const//BigNum BIgNum:: operator / (const int o) const{BigNum ret;BigNum mod;// deal with the BigNum / int//int mod = 0;int i;int left;int right;int mid;memcpy(mod.num, num + l - (o.l - 1), sizeof(int)* (o.l - 1));//mod.l = max(o.l - 1, mod.l);//ret.l = l - o.l + 1;//for (i = l - o.l; i >= 0; i--)//for (i = l - 1; i >= 0; i--) // for int{mod = mod * MOD + num[i];left = 0;right = MOD;while (left < right - 1){mid = (left + right) >> 1;if (mod < o * mid){right = mid;}else {left = mid;}}mod = mod - o * left;ret.num[i] = left;}return ret.MoveZero();}BigNum BigNum::sqrt() const{int i;int j;BigNum ret;BigNum n;BigNum tmp;for (i = l - 1; i >= 0; i--){int tt[] = {num[i] / 100 , num[i] % 100};for (j = 0; j < 2; j++){n = n * 100 + tt[j];int k = 0;tmp = ret * 20;while (1){tmp.num[0]++;if (n < tmp * (k + 1)){break;}k++;}tmp.num[0]--;n = n - tmp * k;ret = ret * 10 + k;}}return ret;}void BigNum::Print(char * s = "/n"){ int i; printf("%d", num[l - 1]); for (i = l - 2; i >= 0; i--) { printf("%04d", num[i]); } printf("%s", s); return ;}