#include<stdio.h>
int main()
{
    int abcd,n,a,b,c,d;
    //1000<=abcd<=9999
    scanf("%d",&abcd);
    d=abcd%10;
    c=abcd/10%10;
    b=abcd/100%10;
    a=abcd/1000;
    n=d*1000+c*100+b*10+a;
    printf("%d",n);
    return 0;
}

#include<stdio.h> int main() { int a,b,c,d,abcd,sum;//简单易懂； scanf("%d",&abcd); a=abcd/1000; b=(abcd-a1000)/100; c=(abcd-a1000-b100)/10; d=(abcd-a1000-b100-c10); sum=d1000+c100+b*10+a; printf("%d",sum); return 0; }

#include <stdio.h> int main() { int x; scanf("%d",&x); int a; int b=0; while(x>0) { a=x%10; b=b*10+a; x=x/10; } printf("%d",b); return 0; }

#include <stdio.h> int main() { int m, a, b, c, d; while(scanf("%d",&m)!=EOF) { if(m>=1000&&m<=9999) { a = m/1000; b = m/100%10; c = m/10%10; d = m%10; if(d==0) printf("%d\n",100c+10b+a); else printf("%d\n",1000d+100c+10*b+a); } } return 0; }

#include<stdio.h> int main(){ int sb ,c; ** c=0;** scanf("%d",&sb); ** while(sb!=0){c=c*10+sb%10;sb/=10;}** ** //TODO ** printf("%d",c);

return 0; }

#include <stdio.h>

int main() { int n;

scanf("%d", &n);

// 反转数字 int reversed = 0; while (n > 0) { reversed = reversed * 10 + n % 10; // 取出最后一位并加入反转数 n /= 10; // 去掉最后一位 }

// 输出反转后的值 printf("%d\n", reversed);

return 0;

}

#include <stdio.h>

int main() { int n;

scanf("%d", &n);

// 反转数字 int reversed = 0; while (n > 0) { reversed = reversed * 10 + n % 10; // 取出最后一位并加入反转数 n /= 10; // 去掉最后一位 }

// 输出反转后的值 printf("%d\n", reversed);

return 0; }

#include <stdio.h>

#include "math.h"
int main()
{
    int nb(int a);
    int a,n,i;
    scanf("%d",&a);
    n=nb(a);
    i=n;
    int num[n],b=a;
    while (i>0)
    {
        num[i]=(int)(b/(int)pow(10,i-1));
        b=b-num[i]*(int)pow(10,i-1);
        i--;
    }

    i=1;
    int c;
    while (i<=n)
    {
        c+=num[i]*pow(10,n-i+1)/10;
        i++;
    }
    printf("%d",c);


    return 0;
}

int nb(int a)
{
    int nb=0,ns=1;
    while(a/ns!=0)
    {
        nb++;
        ns=10*ns;
    }
    return nb;
}
//

#include<stdio.h>
int main()
{
    int abcd,n,a,b,c,d;
    //1000<=abcd<=9999
    scanf("%d",&abcd);
    d=abcd%10;
    c=abcd/10%10;
    b=abcd/100%10;
    a=abcd/1000;
    n=d*1000+c*100+b*10+a;
    printf("%d",n);
    return 0;
}

#include<stdio.h> int main(){ int a,b,c,d,N; scanf("%d",&N); a=N/1000; b=N/100%10; c=N/10%10; d=N/1%10; printf("%d",d1000+c100+b*10+a); return 0;

}

#include<stdio.h>
int main(){
    int n,a,b,c,d,sum=0;
    scanf("%d",&n);
    a=n%10;
    b=n/10%10;
    c=n/100%10;
    d=n/1000;
    sum=a*1000+b*100+c*10+d;
    printf("%d",sum);
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
	int s, a;
	while(cin >> s)
	{
		a = s / 1000;//ge
		a += s / 100 % 10 * 10;//shi
		a += s / 10 % 10 * 100;//bai
		a += s % 10 * 1000;//qian
		cout << a << endl;
	}
	return 0;
}

#include<stdio.h>

int main(){

int n,a,b=0;

scanf("%d",&n);

while(n!=0){

a=n%10;

b=(b*10)+a;

n=n/10; } printf("%d",b);

return 0; }

#include<stdio.h> int main() { int n; int a,b,c,d; scanf("%d",&n); a=n%10; b=(n%100)/10; c=(n%1000)/100; d=n/1000; printf("%d",a1000+b100+c*10+d); return 0; }