问题描述
你能帮我找出用vector实现的栈打印逆序的错误吗?
我遇到了分段错误
#include <iostream>
#include<vector>
using namespace std;
class stack{
public :
int top;
vector<int> data;
bool isempty(){return top == -1;}
void push(int x){data[++top] = x;}
void pop(){--top;}
int topper(){return data[top];}
};
int main()
{
stack s;
int n;
s.top = -1;
cout << "enter the number of integers" << endl;
cin >> n;
for(int i =0; i < n; i ++){
s.push(i);
}
while(!s.isempty()){
cout << s.topper();
s.pop();
}
return 0;
}
解决方法
出现此问题,因为默认情况下 vector
具有 size = 0
。
您可以在向其中添加值之前调整向量的大小,如下所示:
#include <iostream>
#include<vector>
using namespace std;
class stack {
public:
int top;
vector<int> data;
bool isempty() { return top == -1; }
void push(int x) { data.resize(++top+1); data[top] = x; }
void pop() { --top; }
int topper() { return data[top]; }
};
int main()
{
stack s;
int n;
s.top = -1;
cout << "enter the number of integers" << endl;
cin >> n;
for (int i = 0; i < n; i++) {
s.push(i);
}
while (!s.isempty()) {
cout << s.topper();
s.pop();
}
return 0;
}
或者您可以像这样使用 vectors
的内置功能,我认为这是更好的解决方案:
#include <iostream>
#include<vector>
using namespace std;
class stack {
public:
vector<int> data;
bool isempty() { return data.size() == 0; }
void push(int x) { data.push_back(x); }
void pop() { data.pop_back(); }
int topper() { return data.back(); }
};
int main()
{
stack s = stack();
int n;
cout << "enter the number of integers" << endl;
cin >> n;
for (int i = 0; i < n; i++) {
s.push(i);
}
while (!s.isempty()) {
cout << s.topper();
s.pop();
}
return 0;
}