7-19 求链式线性表的倒数第K项 (20分)
AC代码
#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
vector<int> v;
int main(){
int k, num;
scanf("%d", &k);
while (scanf("%d", &num) && num >= 0)
v.push_back(num);
if (k > v.size() || k <= 0){
printf("NULL");
return 0;
}
printf("%d", v[v.size()-k]);
return 0;
}