标签：总结 int top else 错题 push include 考试 size
错题总结
T1:P1739 表达式括号匹配
错误代码：
#include<iostream>
#include<stack>
using namespace std;
int main() {
stack<char> q;
string a;
cin>>a;
for(int i=0;i<a.size()-1;i++)
{
if(a[i]=='(')
q.push('(');
else if(a[i]==')')
if(q.size())
q.pop();
else
{
cout<<"No";
return 0;
}
}
if(!q.size())
cout<<"YES";
else
cout<<"NO";
return 0;
}
代码错误点
else
{
cout<<"No";
return 0;
}
修改方案
cout<<"No";//错误代码
cout<<"NO";//更改后代码
正确代码
#include<iostream>
#include<stack>
using namespace std;
int main() {
stack<char> q;
string a;
cin>>a;
for(int i=0;i<a.size()-1;i++)
{
if(a[i]=='(')
q.push('(');
else if(a[i]==')')
if(q.size())
q.pop();
else
{
cout<<"NO";
return 0;
}
}
if(!q.size())
cout<<"YES";
else
cout<<"NO";
return 0;
}
T2:[ABC328D] Take ABC
错误代码：
#include <cstring>
#include <iostream>
#include <stack>
using namespace std;
int main()
{
string a;
cin >> a;
stack<char> q;
int len = a.size();
for (int i = 0; i < len; i++)
{
if (a[i] == 'A' || a[i] == 'B')
{
q.push(a[i]);
}
else if (a[i] == 'C')
{
if (q.top() == 'B' && q.size() > 2)
{
q.pop();
if (q.size())
{
if (q.top() == 'A')
{
q.pop();
continue;
}
else
{
q.push('B');
q.push(a[i]);
}
}
else
{
q.push('B');
q.push(a[i]);
}
}
else
{
q.push(a[i]);
}
}
}
string ans = "";
while (q.size())
{
ans = q.top() + ans;
q.pop();
}
cout << ans;
return 0;
}
代码错误点
if (q.top() == 'B' && q.size() > 2)
修改方案
if (q.top() == 'B' && q.size() > 2) //错误代码
//正确代码
if (q.size())
if(q.top() == 'B')
{
//中间一样
}else
{
q.push(a[i]);
}
else
{
q.push(a[i]);
}
正确代码
#include <cstring>
#include <iostream>
#include <stack>
using namespace std;
int main()
{
string a;
cin >> a;
stack<char> q;
int len = a.length();
for (int i = 0; i < len; i++)
{
if (a[i] == 'A' || a[i] == 'B')
{
q.push(a[i]);
}
else if (a[i] == 'C')
{
if (q.size())
{
if (q.top() == 'B')
{
q.pop();
if (q.size())
{
if (q.top() == 'A')
{
q.pop();
continue;
}
else
{
q.push('B');
q.push(a[i]);
}
}
else
{
q.push('B');
q.push(a[i]);
}
}
else
{
q.push(a[i]);
}
}
else
{
q.push(a[i]);
}
}
}
string ans = "";
while (q.size())
{
ans = q.top() + ans;
q.pop();
}
cout << ans;
return 0;
}
别问我为什么要发，问就是老师逼的
标签：总结,
int,
top,
else,
错题,
push,
include,
考试,
size
From： https://www.cnblogs.com/basibatuo/p/18314298