1 #include<cstdio> 2 #include<cstring> 3 #include<algorithm> 4 #define LL long long 5 #define rg register 6 #define N 200010 7 using namespace std; 8 int n,m,len,a[N],b[N],t[N]; 9 char s[N],s2[N]; 10 inline int read(){ 11 int k=0,f=1; char c=getchar(); 12 while(c<'0'||c>'9')c=='-'&&(f=-1),c=getchar(); 13 while('0'<=c&&c<='9')k=k*10+c-'0',c=getchar(); 14 return k*f; 15 } 16 int main(){ 17 scanf("%s",s+1); scanf("%s",s2+1); 18 n=strlen(s+1); m=strlen(s2+1); len=n+m+1; 19 if(n<m){ 20 for(rg int i=1;i<=m;i++) a[m-i+1]=s2[i]-'0'; 21 for(rg int i=1;i<=n;i++) b[n-i+1]=s[i]-'0'; 22 swap(n,m); 23 } 24 else{ 25 for(rg int i=1;i<=n;i++) a[n-i+1]=s[i]-'0'; 26 for(rg int i=1;i<=m;i++) b[m-i+1]=s2[i]-'0'; 27 } 28 for(rg int i=1;i<=m;i++){ 29 for(rg int j=1;j<=n;j++) 30 t[i+j-1]+=b[i]*a[j]; 31 } 32 for(rg int i=1;i<=len;i++){ 33 int tmp=t[i]/10; 34 t[i]-=tmp*10; 35 t[i+1]+=tmp; 36 } 37 while(!t[len]) len--; 38 for(rg int i=len;i;i--) printf("%d",t[i]); puts(""); 39 return 0; 40 }