JZOJ 1494. 密码

留个高精度的模板

(Code)

#include<cstdio>
#include<cstring>
using namespace std;

int n , a[5005] , b[5005] , c[5005];

inline void Mul()
{
	while (c[0]) c[c[0]--] = 0;
	for(register int i = 1; i <= a[0]; i++)
	{
		int g = 0;
		for(register int j = 1; j <= b[0]; j++)
		{
			c[i + j - 1] += a[i] * b[j] + g;
			g = c[i + j - 1] / 10;
			c[i + j - 1] %= 10;
		}
		c[i + b[0]] += g;
	}
	c[0] = a[0] + b[0];
	while (c[c[0]] == 0 && c[0] > 1) c[0]--;
	for(register int i = 1; i <= c[0]; i++) a[i] = c[i];
	a[0] = c[0];
}

int main()
{
	char s[50];
	a[a[0] = 1] = 1;
	scanf("%d" , &n);
	for(; n; n--)
	{
		scanf("%s" , s);
		int len = strlen(s);
		b[0] = 0;
		for(register int i = len - 1; i >= 0; i--) b[++b[0]] = s[i] - '0';
		Mul();
	}
	for(register int i = a[0]; i; i--) printf("%d" , a[i]);
}