75分求助

_TeaClaudz_ @ 2023-08-15 22:11:42

#include<bits/stdc++.h>
using namespace std;

int a[100], s[100], la, ls;

void add() {
    int x = 0;
    for(int i = 0; i < la; ++i) {
        s[i] += a[i] + x;
        x = s[i] / 10;
        s[i] %= 10;
    }
    if(la > ls) ls = la;
    if(x) {
        s[la++] += x;
    }
    while(s[ls - 1] == 0 && ls > 1) ls--;
}

void mul(int n) {
    int x = 0;
    for(int i = 0; i < la; ++i) {
        a[i] = a[i] * n + x;
        x = a[i] / 10;
        a[i] %= 10;
    }
    if(x) a[la++] = x;
    while(a[la - 1] == 0 && la > 1) la--;
    return;
}

int main() {
    int n, n2;
    ls = 1;
    s[0] = 0;
    cin >> n;
    n2 = n;
    while(n2) {
        a[la++] = n2 % 10;
        n2 /= 10;
    }
    for(int i = 1; i <= n; ++i) {
        memset(a, 0, sizeof(a));
        la = 1;
        a[0] = 1;
        for(int j = i; j >= 1; --j) {
            mul(j);
        }
        add();
    }
    for(int i = ls - 1; i >= 0; --i) {
        cout << s[i];
    }
    return 0;
}

by forest1145141919810 @ 2023-08-22 20:41:01

@luoyuwei 虽然我不知道你错哪里了，但是我可以提供一个更好的板子

by forest1145141919810 @ 2023-08-22 20:42:21

#include<bits/stdc++.h>
using namespace std;
struct Num{
    #define LEN 105
    int num[LEN],cnt,f;
    inline int getnum(int x[],int cnt,int f){
        int num=0;
        for(int i=cnt;i>=1;i--) 
            num=num*10+x[i];
        return num;
    }
    inline void copy(int x1[], int cnt1, int f1, int x2[], int& cnt2, int& f2) {//把高精度数x1完全复制给高精度数ans
        for (int i = 1; i <= cnt1; i++) x2[i] = x1[i];
        cnt2 = cnt1; f2 = f1;
    }template<typename T>
    inline void copynum(int x[],int &cnt,int &f,T num){
        if(num==0) {x[1]=0,cnt=1,f=1;return;}
        if(num<0) f=-1,num=-num;else f=1;cnt=0;
        while(num>0) x[++cnt]=num%10,num/=10;
        while(x[cnt]==0&&cnt>0) cnt--;
        if(cnt==0) x[++cnt]=0;
    }
    inline bool ismax(int x1[], int cnt1, int f1, int x2[], int cnt2, int f2) {//判断数x1是不是更大
        if (f1 > f2) return true;
        else if (cnt1 > cnt2) return true;
        else if (f1 < f2) return false;
        else if (cnt1 < cnt2) return false;
        for (int i = cnt1; i >= 1; i--){
            if (x1[i] < x2[i]) return false;
            else if(x1[i] > x2[i]) return true;
        }
        return true;
    }
    inline bool ismin(int x1[], int cnt1, int f1, int x2[], int cnt2, int f2) {//判断数x1是不是更小
        if (f1 > f2) return false;
        else if (cnt1 > cnt2) return false;
        else if (f1 < f2) return true;
        else if (cnt1 < cnt2) return true;
        for (int i = cnt1; i >= 1; i--){
            if (x1[i] > x2[i]) return false;
            else if(x1[i] < x2[i]) return true;
        } 
        return true;
    }
    inline void add(int x1[],int cnt1,int x2[],int cnt2,int ans[],int &cnt){
        int anscnt=cnt;int anst[LEN];int x=0;
        for(int i=1;i<=cnt;i++) anst[i]=ans[i];
        int len=max(cnt1,cnt2);anscnt=0;
        if(len==cnt1) for(int i=cnt2+1;i<=len;i++) x2[i]=0;
        else for(int i=cnt1+1;i<=len;i++) x1[i]=0;
        for(int i=1;i<=len;i++){
            anst[++anscnt]=(x1[i]+x2[i]+x)%10;
            x=(x1[i]+x2[i]+x)/10;
        }
        if(x>0) anst[++anscnt]=x;
        while(!anst[anscnt]&&anscnt>0) anscnt--;
        if(anscnt==0) anscnt=1;cnt=anscnt;
        for(int i=1;i<=anscnt;i++) ans[i]=anst[i];
    }
    inline void minus(int x1[],int cnt1,int x2[],int cnt2,int anst[],int &cnt,int &ansf){
        int cntans=cnt;int ans[LEN];int f=ansf;
        for(int i=1;i<=cnt;i++) ans[i]=anst[i];
        if (ismin(x1, cnt1, 1, x2, cnt2, 1)) {
            copy(x2, cnt2, 1, ans, cntans, f); f = -f;
            for (int i = cnt1; i >= 1; i--) {
                if (ans[i] < x1[i]) {
                    int cnt = i + 1; ans[i] = ans[i] + 10 - x1[i];
                    while (ans[cnt] == 0 && cnt <= cntans) ans[cnt] = 9, cnt++;
                    ans[cnt]--; while (ans[cntans] == 0) cntans--;
                }
                else ans[i] -= x1[i];
            }while (cntans > 0 && ans[cntans] == 0) cntans--; if (cntans == 0) cntans++;
        }
        else {
            copy(x1, cnt1, 1, ans, cntans, f);
            for (int i = cnt2; i >= 1; i--) {
                if (ans[i] < x2[i]) {
                    int cnt = i + 1; ans[i] = ans[i] + 10 - x2[i];
                    while (ans[cnt] == 0 && cnt <= cntans) ans[cnt] = 9, cnt++;
                    ans[cnt]--; while (ans[cntans] == 0) cntans--;
                }
                else ans[i] -= x2[i];
            }while (ans[cntans] == 0) cntans--; if (cntans == 0) cntans++;
        }
        cnt=cntans;ansf=f;if(cnt==1&&ans[1]==0) ansf=1;
        for(int i=1;i<=cntans;i++) anst[i]=ans[i];
    }
    inline void multiply(int x1[],int cnt1,int f1,int x2[],int cnt2,int f2,int ans[],int &cnt,int &f){
        f=f1*f2;cnt=cnt1+cnt2+1;int anst[LEN],ansf=f,cntans=cnt;
        for(int i=1;i<=cntans;i++) anst[i]=0;
        for(int i=1;i<=cnt1;i++){
            int temp=0;
            for(int j=1;j<=cnt2;j++){
                anst[i+j-1]=(x1[i]*x2[j]+temp+anst[i+j-1]);
                temp=anst[i+j-1]/10;
                anst[i+j-1]%=10;
            }
            anst[i+cnt2]=temp;
        }
        while(anst[cntans]==0&&cntans>0) cntans--;
        if(cntans==0) cntans=1,ansf=1;
        for(int i=1;i<=cntans;i++) ans[i]=anst[i];
        cnt=cntans;f=ansf;return;
    }
    inline void operator += (Num b){
        if (f < 0 && b.f>0) minus(b.num, b.cnt, num, cnt, num, cnt, f);
        else if (f > 0 && b.f < 0) minus(num, cnt, b.num, b.cnt, num, cnt, f);
        else {add(num, cnt, b.num, b.cnt, num, cnt); }
    }
    inline void operator -= (Num b){
        if (b.f < 0 && f>0) { f = 1; add(num, cnt, b.num, b.cnt, num, cnt); }
        else if (f < 0 && b.f>0) { f = -1; add(num, cnt, b.num, b.cnt, num, cnt); }
        else if (f > 0 && b.f > 0) minus(num, cnt, b.num, b.cnt, num, cnt, f);
        else if (f < 0 && b.f < 0) minus(b.num, b.cnt, num, cnt, num, cnt, f);
    }
    inline void operator *= (Num b){multiply(num,cnt,f,b.num,b.cnt,b.f,num,cnt,f);}
    inline Num operator + (Num b){
        Num c;if (f < 0 && b.f>0) minus(b.num, b.cnt, num, cnt, c.num, c.cnt, c.f);
        else if (f > 0 && b.f < 0) minus(num, cnt, b.num, b.cnt, c.num, c.cnt, c.f);
        else {add(num, cnt, b.num, b.cnt, c.num, c.cnt); }return c;
    }
    inline Num operator - (Num b){
        Num c;if (b.f < 0 && f>0) { f = 1; add(num, cnt, b.num, b.cnt, c.num, c.cnt); }
        else if (f < 0 && b.f>0) { f = -1; add(num, cnt, b.num, b.cnt, c.num, c.cnt); }
        else if (f > 0 && b.f > 0) minus(num, cnt, b.num, b.cnt, c.num, c.cnt, c.f);
        else if (f < 0 && b.f < 0) minus(b.num, b.cnt, num, cnt, c.num, c.cnt, c.f);
        return c;
    }
    inline Num operator * (Num b){
        Num c;
        multiply(num,cnt,f,b.num,b.cnt,b.f,c.num,c.cnt,c.f);
        return c;
    }
    inline void operator = (Num b){copy(b.num,b.cnt,b.f,num,cnt,f);}
    template<typename T>inline void operator = (T b){copynum(num,cnt,f,b);}
    inline void operator ++ (){
        Num c;c=1;
        if (f < 0 && c.f>0) minus(c.num, c.cnt, num, cnt, num, cnt, f);
        else if (f > 0 && c.f < 0) minus(num, cnt, c.num, c.cnt, num, cnt, f);
        else {add(num, cnt, c.num, c.cnt, num, cnt); }
    }
    inline void operator -- (){
        Num c;c=-1;
        if (f < 0 && c.f>0) minus(c.num, c.cnt, num, cnt, num, cnt, f);
        else if (f > 0 && c.f < 0) minus(num, cnt, c.num, c.cnt, num, cnt, f);
        else {add(num, cnt, c.num, c.cnt, num, cnt); }
    }
    inline bool operator >= (Num b){return ismax(num,cnt,f,b.num,b.cnt,b.f);}
    template<typename T>inline bool operator >= (T b){
        Num c;c=b;return ismax(num,cnt,f,c.num,c.cnt,c.f);
    }
    inline bool operator <= (Num b){return ismin(num,cnt,f,b.num,b.cnt,b.f);}
    template<typename T>inline bool operator <= (T b){
        Num c;c=b;return ismin(num,cnt,f,c.num,c.cnt,c.f);
    }
    inline bool operator == (Num b){
        return ismax(num,cnt,f,b.num,b.cnt,b.f)&&ismin(num,cnt,f,b.num,b.cnt,b.f);
    }
    template<typename T>inline bool operator == (T b){
        Num c;c=b;
        return ismin(num,cnt,f,c.num,c.cnt,c.f)&&ismax(num,cnt,f,c.num,c.cnt,c.f);
    }
    inline bool operator > (Num b){return !ismin(num,cnt,f,b.num,b.cnt,b.f);}
    inline bool operator < (Num b){return !ismax(num,cnt,f,b.num,b.cnt,b.f);}
    template<typename T>inline bool operator > (T b){
        Num c;c=b;return !ismin(num,cnt,f,c.num,c.cnt,c.f);
    }
    template<typename T>inline bool operator < (T b){
        Num c;c=b;return !ismax(num,cnt,f,c.num,c.cnt,c.f);
    }
    inline bool operator ! (){
        Num c;copy(num,cnt,f,c.num,c.cnt,c.f);
        if(c==0) return true;
        return false;
    }
};
inline int GetNum(Num a){return a.getnum(a.num,a.cnt,a.f);}
inline void init(Num &a){a.cnt=1;a.f=1;}
inline void read(Num &a){
    a.cnt=0;a.f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-') a.f=-a.f;ch=getchar();}
    while(ch>='0'&&ch<='9'){a.num[++a.cnt]=ch-'0';ch=getchar();}
    for(int i=1;i<=a.cnt/2;i++) swap(a.num[i],a.num[a.cnt-i+1]);
}
inline void write(Num x){
    if(x.f<0) putchar('-');
    for(int i=x.cnt;i>=1;i--) 
        putchar(x.num[i]+'0');
    putchar('\n');return;
}
#define int Num
#define long long Num
#define __int128 Num
#define ui Num
#define ull Num
int s,n;
signed main(){
    read(n);s=0;int i;
    for(i=1;i<=n;++i){
        int jie,j;jie=1;
        for(j=1;j<=i;++j) jie*=j;
        s+=jie;
    }write(s);
    return 0;
}

最上面结构体里的是封装好了的高精，在主函数里用int算就可以了（我把int也重定义了），很简单的

by whoishe @ 2023-08-22 20:52:58

你可以参考我的代码

#include<bits/stdc++.h>
using namespace std;
int s[100],sum[100];
void cheng(int a[],int b){
    int a1[100] = {};
    for(int i=0;i<100;i++){
        a1[i]+=a[i]*b;
        a1[i+1]+=a1[i]/10%10;
        a1[i+2]+=a1[i]/100;
        a1[i]=a1[i]%10;
    }
    for(int i=0;i<100;i++){
        a[i]=a1[i];
    }
    return;
}
int jia(int s[],int s1[]){
    int s2[100]={};
    for(int i=0;i<99;i++){
        s2[i]+=s[i]+s1[i];
        s2[i+1]+=s2[i]/10;
        s2[i]=s2[i]%10;
    }
    for(int i=0;i<100;i++){
        s[i]=s2[i];
    }
}
int main(){
    int n;
    s[0]=1;
    cin>>n;
    for(int j=n;j>0;j--){
        for(int k=0;k<100;k++){
            s[k]=0;
        }
        s[0]=1;
        for(int i=1;i<=j;i++){
            cheng(s,i);
        }
        jia(sum,s);
    }
    int len=100;
    while(sum[len-1]==0&&len>0){
        len--;
    }
    for(int i=len-1;i>=0;i--){
        cout<<sum[i];
    }
    return 0;
} 

by _TeaClaudz_ @ 2023-08-23 21:11:01

谢谢，找到原因了，忘了 mul() 里面的 x 最后可以超过 10，应该用 while 而不是用 if

by _TeaClaudz_ @ 2023-08-23 21:11:24

此贴结