#include <stdio.h>
#include <stdlib.h>
int main(){
	freopen("reverse.in","r",stdin);
	freopen("reverse.out","w",stdout);
	int a,b,p=1; 
	scanf("%d",&a);
	if(a<=9 && a>=-9)  printf("%d",a);
	else{     
		if(a<0){  	
	       printf("-"); 
	       a=-a;
	    }     
	    while(a%10==0 && p==1){
	    	a=a/10;
	    }
        p=0;
		while(a!=0){
			 b=a%10;
	         printf("%d",b);
	         a=a/10;
		}
	}
	printf("\n");
	system("pause");
	return 0;

}

#include <bits/stdc++.h> using namespace std; int main(){ int x,s=0; cin>>x; while(x!=0){ s=s*10+x%10; x=x/10; } cout<<s; return 0; }

严禁超题解

#include<bits/stdc++.h>
using namespace std;
int XPH(__①__){
    int t=0;
    while(n!=0){
        t=(t*10)+(n%10);
        n/=10;
    }
    return ___②___;
}
int main(){
    freopen(___③___);
    freopen("reverse.out",___④___);
    int n;
    cin>>n;
    cout<<___⑤___(n);
    return 0;
}