#include<cstdio>
#include<cmath>
void Q1()
{
char num[3];
scanf("%s", num);
if(num[0] == num[2])
puts("回文数\n");
else
puts("不是回文数\n");
return ;
}
void Q2()
{
double sum = 0.0, index, x = 1.0;
for(int i = 1; ; i+=2)
{
index = 1.0 / i;
if(fabs(index) < 1e-6)
break;
index *= x;
x = -x;
sum += index;
}
printf("%lf\n\n", sum);
return ;
}
bool prime(int n)
{
if(n < 2)
return false;
for(int i = 2; i < n; i++)
{
if(n % i == 0)
return false;
}
return true;
}
void Q3()
{
for(int i = 100; i < 200; i++)
{
bool ok = prime(i);
if(ok)
printf("%d ", i);
}
puts("\n");
return ;
}
void Q4()
{
int num[10], i;
scanf("%d", &num[0]);
int Max = num[0], index = 0;
for(i = 1; i < 10; i++)
{
scanf("%d", &num[i]);
if(num[i] > Max)
{
Max = num[i];
index = i;
}
}
int temp = num[0];
num[0] = num[index];
num[index] = temp;
for(i = 0; i < 10; i++)
printf("%d%c", num[i], i == 9 ? '\n' : ' ');
puts("");
return ;
}
int main()
{
Q1();
Q2();
Q3();
Q4();
return 0;
}
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