P1303 A*B Problem

Posted 2021-06-27 Kunkun只喝怡宝

代码

#include<bits/stdc++.h>

using namespace std;

char a1[10001],b1[10001];
int a[10001],b[10001],i,x,len,j,c[10001];
int main ()
{
    cin>>a1>>b1;
    int lena=strlen(a1);
	int lenb=strlen(b1);
    for(i=1;i<=lena;i++) a[i]=a1[lena-i]-'0';
    for(i=1;i<=lenb;i++) b[i]=b1[lenb-i]-'0';
	for(i=1;i<=lenb;i++)
		for(j=1;j<=lena;j++)
			c[i+j-1]+=a[j]*b[i];
    for(i=1;i<lena+lenb;i++)
		if(c[i]>9){
			c[i+1]+=c[i]/10;
			c[i]%=10;
		}
	len=lena+lenb;
    while(c[len]==0&&len>1)len--;
    for(i=len;i>=1;i--)cout<<c[i];
    return 0;
}