L1-017. 到底有多二

很简单，不说了

 

#include<iostream>
#include<iomanip>
#include <string.h>
#include <stdio.h>
using namespace std;
int main()
{
char num[52];
cin >> num;
int NumOfTwo = 0, len = strlen(num);
double howEr;
for(int j=0; j<len; j++)
{
if(num[j]=='2')
NumOfTwo++;
}

if(num[len-1]%2==0)
{
if(num[0]=='-')
{
len = len - 1;
howEr = (double)NumOfTwo / len * 1.5 * 2;
}
else
howEr = (double)NumOfTwo / len * 2;
}
else
{ if(num[0]=='-')
{
len = len - 1;
howEr = (double)NumOfTwo / len * 1.5 ;
}
else
howEr = (double)NumOfTwo / len;

}
printf("%0.2lf%%", howEr*100);

return 0;
}