1.问一下,晴神笔记关于一元多项式求导,写a[i] = 0这一步不可省,不然后面的可能无法被覆盖。没太理解这句话
2.还有,如果求导时从高位向地位求导,a[i] = a[i] * i,然后输出时,这样输出a[i], i-1可以么
下面是晴神的代码
#include <cstdio>
int main()
{
int a[1010] = {0};
int k, e, count = 0;
while (scanf("%d%d", &k, &e) != EOF)
{
a[e] = k;
}
a[0] = 0;
for (int i = 1000; i >= 1; i--)
{
a[i-1] = a[i] * i;
a[i] = 0;//------------这一句
if (a[i-1] != 0)
{
count++;
}
}
if (count == 0)
{
printf("0 0");
}
else
{
for (int i = 1000; i >= 0; i--)
{
if (a[i] != 0)
{
printf("%d %d", a[i], i);
count--;
if (count != 0)
{
printf(" ");
}
}
}
}
return 0;
}