```
for (i=0;i<=l;i+=2)
a[i]=1;
```
i+=2 ? ? ?
by sjy_2023 @ 2023-05-14 17:33:25
循环好像都写成+=2了
by sjy_2023 @ 2023-05-14 17:34:48
@[zwbsszd](/user/916051) 改成了
```
i++
```
但还是不行(悲
by None_g @ 2023-05-14 17:36:28
坐标最好分两个数组存
by sjy_2023 @ 2023-05-14 17:37:01
读入坐标是从1开始
by sjy_2023 @ 2023-05-14 17:44:10
哦知道了
找坐标的外层循环也从1开始
而且是到m 不是l
by sjy_2023 @ 2023-05-14 17:55:05
AC:
```
#include<bits/stdc++.h>
using namespace std;
int main()
{
int a[10001],b[10001],q[10001],w[10001];
int x=0,l,m,i,j;
cin>>l>>m;
for (i=1;i<=m;i++)
{
cin>>q[i]>>w[i];
}
for (i=0;i<=l;i++)
a[i]=1;
for (i=1;i<=m;i++)
{
for (j=q[i];j<=w[i];j++)
{
a[j]=0;
}
}
for (i=0;i<=l;i++)
{
if (a[i]==1)
x++;
}
cout<<x;
return 0;
}
```
by sjy_2023 @ 2023-05-14 17:55:35
@[3316084249z](/user/811469)
by sjy_2023 @ 2023-05-14 17:57:31
@[zwbsszd](/user/916051) 欸嘿,谢谢大佬,照着思路改了改,全AC
```
#include<bits/stdc++.h>
using namespace std;
int main()
{
int a[10001],b[10001],c[10001];
int x,l,m,i,j;
x=0;
cin>>l>>m;
for (i=1;i<=m+1;i++)
{
cin>>b[i]>>c[i];
}//b[i] c[i]为一个区域的起始点和终止点的坐标。
for (i=0;i<=l;i++)
a[i]=1;
for (i=1;i<=m;i++)
{
for (j=b[i];j<=c[i];j++)
{
a[j]=0;
}
}
for (i=0;i<=l;i++)
{
if (a[i]==1)
x=x+1;
}
cout<<x;
return 0;
}
```
by None_g @ 2023-05-14 21:01:08
@[zwbsszd](/user/916051) 为什么
```
for (i=1;i<=m+1;i++)
{
cin>>b[i]>>c[i];
}//b[i] c[i]为一个区域的起始点和终止点的坐标。
```
这里
```
i<=m+1
```
在C++软件里F11运行复制粘贴题目中的输入
```
500 3
150 300
100 200
470 471
```
回车没反应,但能通过题目
by None_g @ 2023-05-14 21:08:52