各位大神能帮忙看看我这个该怎么改吗？

cszdls @ 2023-09-22 18:35:00

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

const int MAXT=5000;
char s1[MAXT],s2[MAXT];
int a[MAXT]={0},b[MAXT]={0},c[MAXT]={0}; 

int  main()
{

    int len1,len2,lmax,x=0,n=0;
    scanf("%s%s",&s1,&s2);
    len1=strlen(s1);
    len2=strlen(s2);

    //倒放存入 
    for(int i=0;i<len1;i++)
    {
        a[i]=s1[len1-1-i]-'0';
    }
    for(int i=0;i<len2;i++)
    {
        b[i]=s2[len2-1-i]-'0';
    }

    //运算 
    for(int i=0;i<len1;i++)
    {
        for(int j=0;j<len2;j++)
        {
            n=a[i]*b[j]%10;
            c[i+j]+=n+x;
            x=a[i]*b[j]/10;
        }
    }
    c[len1+len2-1]=x;
    for(int i=0;i<len1;i++)
    {
        for(int j=0;j<len2;j++)
        {
            if(c[i+j]>=10)
            {
                n=c[i+j]%10;
                x=c[i+j]/10;
                c[i+j]=n;
                c[i+j+1]+=x;
            }
        }
    }
    if(c[len1+len2-1]>=10)
    {
        n=c[len1+len2-1]%10;
        c[len1+len2-1]=n+x;
        x=c[len1+len2-1]/10;
    }
    c[len1+len2]=x;
    lmax=len1+len2-1;

    //消零 
    for(int i=0;i<lmax;i--)
    {
        if(c[lmax]==0 and lmax!=0)
        {
            lmax--;
        }
        else
        {
            break;
        }
    }

    //输出 
    for(int i=lmax;i>=0;i--)
    {
        cout<<c[i];
    }

    return 0;
}

by Argvchs @ 2023-09-22 18:38:10

@cszdls

for(int i=0;i<lmax;i--)

by cszdls @ 2023-09-22 18:42:25

@Argvchs 请问那是应该怎么改一下呢？

by LoadingSpace @ 2023-09-22 19:25:57

@cszdls for(int i=0;i<lmax;i--) 有没有一种可能，这样写i一直小于lmax，导致死循环

by shengyeqi @ 2023-09-22 19:30:42

@cszdls

改了一下过了

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

const int MAXT = 50000;
const int BASE = 10;

void multiply(string s1, string s2) {
    int len1 = s1.length();
    int len2 = s2.length();
    vector<int> a(len1);
    vector<int> b(len2);
    vector<int> c(len1 + len2, 0);

    // 将字符转换为数字，并反转字符串以便从低位到高位相乘
    for (int i = 0; i < len1; i++) {
        a[i] = s1[len1 - 1 - i] - '0';
    }

    for (int i = 0; i < len2; i++) {
        b[i] = s2[len2 - 1 - i] - '0';
    }

    // 高精度乘法
    for (int i = 0; i < len1; i++) {
        for (int j = 0, carry = 0; j < len2 || carry; j++) {
            long long product = c[i + j] + (long long)a[i] * (j < len2 ? b[j] : 0) + carry;
            c[i + j] = product % BASE;
            carry = product / BASE;
        }
    }

    // 找到最高非零位
    int lmax = len1 + len2 - 1;
    while (lmax >= 0 && c[lmax] == 0) {
        lmax--;
    }

    // 输出结果
    if (lmax == -1) {
        cout << "0";
    } else {
        for (int i = lmax; i >= 0; i--) {
            cout << c[i];
        }
    }
}

int main() {
    string s1, s2;
    cin >> s1 >> s2;
    multiply(s1, s2);
    return 0;
}

by cszdls @ 2023-09-22 19:50:21

@shen @shengyeqin 谢谢大神，过了，感谢，明白了

by cszdls @ 2023-09-22 19:50:57

@LoadingSpace 谢谢，看到了，已经改好了，感谢帮助

by cszdls @ 2023-09-22 19:51:40

@Argvchs 感谢大神，已经过了

by shengyeqi @ 2023-09-22 19:53:04

@cszdls

求关注

by LoadingSpace @ 2023-09-22 22:09:59

@shengyeqin 你主页链接很好看，关了

by shengyeqi @ 2023-09-23 06:07:26

@LoadingSpace 薛薛