改了改还是不对（~~约等于没改~~）
```c
#include<bits/stdc++.h>
using namespace std;
int main(){
int a=1,b=1;
double num=2.0,i,sum;
cin>>sum;
while(b==1){
if(num>=sum){
b=b-1;
cout<<a;
}
else{
i=num*1.98;
a++;
}
}
return 0;
}
```
by Kvj123456 @ 2021-10-06 08:53:55
```cpp
#include<bits/stdc++.h>
#define int long long
#define rei register int
#define rep(i,x,y) for(rei i = (x);i <= (y);i++)
#define per(i,y,x) for(rei i = (y);i >= (x);i--)
#define grep(i,x) for(rei i = h[x];i ;i = ne[i])
#define dou double
#define mp make_pair
#define X first
#define Y second
#define ls(fadsfdds) t[fadsfdds << 1]
#define rs(fadsfdds) t[fadsfdds << 1 | 1]
#define len(fasd) (t[fasd].r - t[fasd].l + 1)
#define ull unsigned int
using namespace std;
const int N = 1e5 + 5,M = N << 1,P = 131;
int Q;
void read(int &x){
int s = 0,f = 1;char ch = getchar();
while(ch > '9' || ch < '0'){if(ch == '-')f = -1;ch = getchar();}
while(ch <= '9' && ch >= '0')s = s * 10 + ch - '0',ch = getchar();
x = s * f;
}
int step;
dou p = 2,x;
signed main(){
scanf("%lf",&x);
while(x > 0)x -= p,step++,p *= 0.98;
printf("%lld",step);
return 0;
}
```
by yhxfzs @ 2021-10-06 08:58:06
快读！！！大佬大佬
by int4096 @ 2021-10-06 08:59:45
```
#include<bits/stdc++.h>
using namespace std;
int main(){
int a=1;
double num=2.0,sum;
cin>>sum;
while(1){
if(num>=sum){
// b=b-1; ??? 没看懂
cout<<a;
return 0;
}
else{
sum -= num;//每一次减少的距离
num = num*0.98;
a++;
}
}
return 0;
}
```
by yhxfzs @ 2021-10-06 09:10:12
有些变量是没有必要的吧
by LionShiZi @ 2021-10-06 09:15:28
@[Kvj123456](/user/569914) 很明显了
首先，你不能
```cpp
i*=1.98;
```
应该改成
```cpp
i+=num;
num*=0.98;
```
在此之外
你TLE是因为：
```cpp
num=2.0没有变过
应该是i>=sum作为判断条件
```
建议以后用bool来记录
by Luban @ 2021-10-06 09:53:05
@[yhxfzs](/user/207407) 巨佬，甘拜下风
by Kvj123456 @ 2021-10-06 19:09:57
@[可爱小鲁班](/user/113600) 谢谢大佬，回去试一下先
by Kvj123456 @ 2021-10-06 19:10:53
@[yhxfzs](/user/207407) b=b-1相当于retrun 0 我不会用，刚接触没1个月
by Kvj123456 @ 2021-10-06 19:26:04
@[可爱小鲁班](/user/113600) ~~本巨蒻还是没会，不好意思再找dalao了~~
```c
#include<bits/stdc++.h>
using namespace std;
int main(){
int a=1,b=1;
double num=2.0,i,sum;
cin>>sum;
while(i>=sum){
if(num>=sum){
cout<<a;
return 0;
}
else{
i=num*1.98;
a++;
}
}
return 0;
}
```
by Kvj123456 @ 2021-10-06 19:34:05