求调，高精度乘法，有点急

void High_precision_multiplication(string x,string y){
	int a[100], b[100], c[200],len_n, len_m, i, j, w, s, k;
	len_n = x.size();
	len_m = y.size();
	string e=""; 
	for (i=0; i<=len_n - 1; i++)
		a[i] = x[len_n-i-1]-48;
	for (i=0; i<=len_m - 1; i++)
		b[i] = y[len_m-i-1]-48;
	for (i=0; i<=len_n-1; i++) 
		for (j=0; j<=len_m-1; j++) {
			w = i+j;
			s=a[i]*b[j];
			c[w] += s%10;
			c[w+1]+= c[w]/10+s/10;
			c[w]=c[w]%10;
		} 
	k = len_n+len_m;
	while (c[k]==0 && k>0) 
		k--;
	for(i=k; i>=0; i--) 
		cout<< c[i];
}