#include<iostream> #include<vector> using namespace std; int main() { int N; while(cin>>N) { vector<int> vec(N,0); int temp,x; for(unsigned int i=0;i<N;i++) { cin>>temp; vec[i]=temp; } cin>>x; bool flag=false; for(int i=0;i<N;i++) { if(vec[i]==x) { cout<<i<<endl; flag=true; break; } } if(flag==false) cout<<"-1"<<endl; } return 0; }
#include<bits/stdc++.h> //万能头 #include<iostream> #include<cstdio> #include<algorithm> #include<string> using namespace std; int main(){ int n; while(scanf("%d",&n)!=EOF) { int a[n]; int flag=0; for(int i=0;i<n;i++) { scanf("%d",&a[i]); } int x; scanf("%d",&x); for(int i=0;i<n;i++) { if (a[i]==x) { printf("%d\n",i); flag=1; } } if (flag==0) { printf("-1\n"); } } return 0; }
import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); int n = scanner.nextInt(); int[] record = new int[n]; for (int i = 0; i < n; i++) { record[i]=scanner.nextInt(); } int search = scanner.nextInt(); for (int i = 0; i < n; i++) { if (record[i]==search){ System.out.println(i); return; } } System.out.println(-1); } }
//具体步骤在博客:https://blog.csdn.net/qq_44840148/article/details/104656636 import java.util.HashMap; import java.util.Map; import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc=new Scanner(System.in); while(sc.hasNext()){ int n=sc.nextInt(); Map<Integer,Integer> map =new HashMap<>(n); for(int i=0;i<n;i++){ map.put(sc.nextInt(),i); } int x=sc.nextInt(); if(map.containsKey(x)){ System.out.println(map.get(x)); }else { System.out.println(-1); } } } }
#include<bits/stdc++.h> using namespace std; int main() { int n, x, y = -1; int a[200] = { 0 }; while (cin >> n) { for (int i = 0; i < n; i++) { cin >> a[i]; } cin >> x; for (int i = 0; i < n; i++) { if (a[i] == x) { y = i; break; } } cout << y; } return 0; }
#include<iostream> #include<cstdio> using namespace std; const int Maximum = 200; int array[Maximum]; int main(){ int number; int x; bool find = false; cin>>number; for(int i=0; i<number; i++){ cin>>array[i]; } cin>>x; for(int j=0; j<number; j++){ if(x == array[j]){ find = true; cout<<j<<endl; } } if(!find){ cout<<-1<<endl; } return 0; }
#include<stdio.h> int main() { int n,x,flag=-1; scanf("%d",&n); int a[n]; for(int i=0;i<n;i++) { scanf("%d",&a[i]); } scanf("%d",&x); for(int i=0;i<n;i++) { if(a[i]==x) flag=i; } printf("%d",flag); }
#include<iostream> #include<stdio.h> #include<string> #include<algorithm> using namespace std; int main(){ int n; string s=""; while(cin>>n){ for(int i=0;i<n;i++){ int t; scanf("%d",&t); s.append(to_string(t)); s.push_back(' '); //拼接成字符串"1023 1035 1045 ..." } string key; cin>>key; key.push_back(' '); //查找的字符串也要加上空格。 string temp = s.substr(0,s.find(k)+1); int re = count(temp.begin(),temp.end(),' '); //利用<algorithm>库的count方法。 if(temp=="") //没有找到,s.find(k)是-1,temp是空字符串。 cout<<-1<<endl; else cout<<re<<endl; } return 0; }不知道效率如何?
#include <bits/stdc++.h>
using namespace std;
int main(void) {
int n, x;
while (cin >> n) {
vector<int> v(n);
for (int i = 0; i < n; ++i) {
cin >> v[i];
}
cin >> x;
auto it = find(v.begin(), v.end(), x);
it == v.end() ? cout << "-1\n" : cout << int(it - v.begin()) << endl;
}
return 0;
}
//由于规模为200,肯定不会超过范围,输入无序,所以采用顺序遍历即可 #include<iostream> using namespace std; int main(){ int n; while(cin>>n){ int* a=new int[n]; for(int i=0;i<n;i++) cin>>a[i]; int x,pos=-1; cin>>x; for(int i=0;i<n;i++) if(a[i]==x){ pos=i; break; } cout<<pos<<endl; } }
import java.util.*; public class Main { public static void main(String [] args) { Scanner sc=new Scanner(System.in); while(sc.hasNextInt()) { int n=sc.nextInt(); int [] arr=new int[n]; for(int i=0;i<n;i++) { arr[i]=sc.nextInt(); } int x=sc.nextInt(); int index=-1; for(int i=0;i<n;i++) { if(arr[i]==x) { index=i; } } System.out.println(index); } } }
#include <cstdio> int main() { int n; scanf("%d",&n); int arr[210]; for(int i = 0; i < n; ++i){ scanf("%d",&arr[i]); } int x; bool flag = false; scanf("%d",&x); for(int i = 0; i < n; ++i){ if(arr[i] == x){ printf("%d\n",i); flag = true; break; } } if(flag == false) printf("-1\n"); return 0; }
#include <iostream> using namespace std; int main() { int n,x; int a[300]; cin >> n; for(int i=0; i<n; ++i){ cin >> a[i]; } cin >> x; for(int j=0; j<n; ++j){ if(x == a[j]){ cout << j; return 0; } } cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; int main() { vector<int>v; int n; cin>>n; for(int i=0;i<n;i++){ int t; cin>>t; v.push_back(t); } int cha; cin>>cha; auto it=std::find(v.begin(),v.end(),cha); if(it==v.end()) cout<<"-1"<<endl; else{ int d=std::distance(v.begin(),it); cout<<d<<endl; } }