全ACGO最正经题解

大概就是我啥也不想说了，你们直接搬吧

#include <iostream>
using namespace std;
struct node{
    int val;
    node* next;
};
void show_list(node* head){ //遍历输出链表中所有元素
    node* cur = head;
    while(cur != nullptr){
        cout<<cur->val<<" ";
        cur = cur->next;
    }
}
int main(){
    int n;
    cin>>n;
    node* dummy = new node();
    dummy->next = nullptr;
    node* tail = dummy;
    for(int i=0;i<n;i++){
        int num;
        cin>>num;
        node* nd = new node();
        nd->val = num;
        nd->next = nullptr;
        tail->next = nd;
        tail = nd;
    }int m,q;
    cin>>m>>q;
    node* cur = dummy->next;
    while(cur != nullptr){
        if(cur->val == m){
            node* newp = new node();
            newp->val = q;
            newp->next = cur->next;
            cur->next = newp;
            cur = cur->next;
        }
        cur = cur->next;
    }
    show_list(dummy->next);
    return 0;
}