http://120.78.162.102/problem.php?cid=1432&pid=2

http://120.78.162.102/problem.php?id=6241

题解:见代码

/*
*@Author:   STZG
*@Language: C++
*/
#include <bits/stdc++.h>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<string>
#include<vector>
#include<bitset>
#include<queue>
#include<deque>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
//#define DEBUG
#define RI register int
using namespace std;
typedef long long ll;
//typedef __int128 lll;
const int N=100000+100;
const int MOD=1e9+7;
const double PI = acos(-1.0);
const double EXP = 1E-8;
const int INF = 0x3f3f3f3f;
int t,n,m,k,q;
int a[N];
int main()
{
#ifdef DEBUG
	freopen("input.in", "r", stdin);
	//freopen("output.out", "w", stdout);
#endif
    while(~scanf("%d",&n)){
        t=0;
        for(int i=1;i<=n;i++){
            scanf("%d",&a[i]);
            if(i!=1&&a[i]<a[i-1]){
                    t++;
            }
        }
        if(t==1||t==0){
            cout << "Yes" << endl;
        }else{
            cout << "No" << endl;
        }
    }

    //cout << "Hello world!" << endl;
    return 0;
}

C++版本二

加强重判

/*
*@Author:   STZG
*@Language: C++
*/
#include <bits/stdc++.h>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<string>
#include<vector>
#include<bitset>
#include<queue>
#include<deque>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
//#define DEBUG
#define RI register int
using namespace std;
typedef long long ll;
//typedef __int128 lll;
const int N=100000+100;
const int MOD=1e9+7;
const double PI = acos(-1.0);
const double EXP = 1E-8;
const int INF = 0x3f3f3f3f;
int t,n,m,k,q;
int a[N];
int b[N];
int main()
{
#ifdef DEBUG
	freopen("input.in", "r", stdin);
	//freopen("output.out", "w", stdout);
#endif
    while(~scanf("%d",&n)){
        t=0;
        for(int i=1;i<=n;i++){
            scanf("%d",&a[i]);
            b[i]=a[i];
            if(i!=1&&a[i]<a[i-1]){
                    t++;
            }
        }
        if(t==1||t==0){
            if(t==1){
                for(int i=2;i<=n;i++){
                    if(a[i]<a[i-1]){
                        swap(a[i],a[i-1]);
                        //break;
                    }
                }
                for(int i=2;i<=n;i++){
                    if(a[i]<a[i-1]){
                        t=0;
                        break;
                    }
                }
                q=1;
                for(int i=n;i>=2;i--){
                    if(b[i]<b[i-1]){
                        swap(b[i],b[i-1]);
                        //break;
                    }
                }
                for(int i=2;i<=n;i++){
                    if(b[i]<b[i-1]){
                        q=0;
                        break;
                    }
                }
                if(t||q){
                    cout << "Yes" << endl;
                }else{
                    cout << "No" << endl;
                }
            }else{
                cout << "Yes" << endl;
            }
        }else{
            cout << "No" << endl;
        }
    }

    //cout << "Hello world!" << endl;
    return 0;
}