回文数-蓝桥杯

//Q21-回文数
//蓝桥杯

#include<stdio.h>

int Result;

int Check(int num, int length){
    int temp,r1;
    
    int check=num;
    
    if(length==5){
        check/=10;
        temp=(check%10)*10;
        check/=10;
        temp+=check%10;
        num*=100;
        
        num+=temp;
    }
    else{
        temp=(check%10)*100;
        check/=10;
        temp+=(check%10)*10;
        check/=10;
        temp+=check;
        num*=1000;
        
        num+=temp;
    }
    
    r1=num;
    temp=0;
    
    while(r1){
        temp+=r1%10;
        r1/=10;
    }

    if(temp==Result){
         printf("%d\n",num);
         return 1;
    }
    else return 0;
}

int main(void){
    scanf("%d",&Result);
    
    int r1,result=0,temp;
    
    for(r1=100;r1<=999;r1++){
        if(Check(r1,5))
            result++;
    }
    
    for(r1=100;r1<=999;r1++){
        if(Check(r1,6))
            result++;
    }
    
    if(result==0) printf("-1\n");
    
    return 0;
}