#include<bits/stdc++.h>
#define pb(a) push_back(a)
#define ms(x,y) memset(x,y,sizeof(x))
#define sci(a) scanf("%d",&a) 
#define scl(a) scanf("%lld",&a)
#define scd(a) scanf("%lf",&a) 
#define ll long long 
using namespace std;
/* --------------- fast io --------------- */ // begin
namespace Fread{
const int SIZE=1<<20;
char buf[SIZE],*S,*T;
inline char getchar(){
	if(S==T){
		T=(S=buf)+fread(buf,1,SIZE,stdin);
		if(S==T)return EOF;
	}
	return *S++;
}
}//namespace Fread
namespace Fwrite{
const int SIZE=1<<20;
char buf[SIZE],*S=buf,*T=buf+SIZE;
inline void flush(){
	fwrite(buf,1,S-buf,stdout);
	S=buf;
}
inline void putchar(char c){
	*S++=c;
	if(S==T)flush();
}
struct _{
	~_(){flush();}
}__;
}//namespace Fwrite

#ifdef ONLINE_JUDGE
	#define getchar Fread::getchar
	#define putchar Fwrite::putchar
#endif

template<typename T>inline void read(T& x){
	x=0;int f=1;
	char c=getchar();
	while(!isdigit(c)){if(c=='-')f=-1;c=getchar();}
	while(isdigit(c))x=x*10+(c-'0'),c=getchar();
	x*=f;
}
template<typename T>inline void write(T x,bool _enter=0,bool _space=0){
	if (!x)putchar('0');else{
		if(x<0)putchar('-'),x=-x;
		static char dig[41];
		int top=0;
		while(x)dig[++top]=(x%10)+'0',x/=10;
		while(top)putchar(dig[top--]);
	}
	if(_enter)putchar('\n');
	if(_space)putchar(' ');
}

namespace Fastio{
struct reader{
	template<typename T>reader& operator>>(T& x){::read(x);return *this;}
	reader& operator>>(char& c){
		c=getchar();
		while(c=='\n'||c==' ')c=getchar();
		return *this;
	}
	reader& operator>>(char* str){
		int len=0;
		char c=getchar();
		while(c=='\n'||c==' ')c=getchar();
		while(c!='\n'&&c!=' ')str[len++]=c,c=getchar();
		str[len]='\0';
		return *this;
	}
}cin;
const char endl='\n';
struct writer{
	template<typename T>writer& operator<<(T x){::write(x,0,0);return *this;}
	writer& operator<<(char c){putchar(c);return *this;}
	writer& operator<<(const char* str){
		int cur=0;
		while(str[cur])putchar(str[cur++]);
		return *this;
	}
}cout;
}//namespace Fastio
#define cin Fastio::cin
#define cout Fastio::cout
#define endl Fastio::endl
/* --------------- fast io --------------- */ // end

const int maxn=100005;
int main(){
		//#define int ll
		int d,t,s;
	while(scanf("%d %d %d",&d,&t,&s)!=EOF){

		
		if(t*s>=d)
			puts("Yes");
		else
			puts("No");
	 }
	return 0;
} 
#include <bits/stdc++.h>
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define rep(i,n) for (int i=0;i<(int)(n);i++)
#define codefor int test;scanf("%d",&test);while(test--)
#define yn(ans) if(ans)printf("Yes\n");else printf("No\n")
#define YN(ans) if(ans)printf("YES\n");else printf("NO\n")
#define umap unordered_map
#define uset unordered_set
using namespace std;
using ll = long long;
const int MOD=1000000007;
//入力系
void scan(int& a){scanf("%d",&a);}
void scan(long long& a){scanf("%lld",&a);}
template<class T> void scan(T& a){cin>>a;}
template<class T> void scan(vector<T>& vec){for(auto&& it:vec)scan(it);}
void in(){}
template <class Head, class... Tail> void in(Head& head, Tail&... tail){scan(head);in(tail...);}
//出力系
void print(const int& a){printf("%d",a);}
void print(const long long& a){printf("%lld",a);}
void print(const double& a){printf("%.15lf",a);}
template<class T> void print(const T& a){cout<<a;}
template<class T> void print(const vector<T>& vec){if(vec.empty())return;print(vec[0]);for(auto it=vec.begin();++it!= vec.end();){putchar(' ');print(*it);}}
void out(){putchar('\n');}
template<class T> void out(const T& t){print(t);putchar('\n');}
template <class Head, class... Tail> void out(const Head& head,const Tail&... tail){print(head);putchar(' ');out(tail...);}
//デバッグ系
template<class T> void dprint(const T& a){cerr<<a;}
template<class T> void dprint(const vector<T>& vec){if(vec.empty())return;cerr<<vec[0];for(auto it=vec.begin();++it!= vec.end();){cerr<<" "<<*it;}}
void debug(){cerr<<endl;}
template<class T> void debug(const T& t){dprint(t);cerr<<endl;}
template <class Head, class... Tail> void debug(const Head& head, const Tail&... tail){dprint(head);cerr<<" ";debug(tail...);}

int main(){
    string s;
    cin>>s;
    if(s=="zyxwvutsrqponmlkjihgfedcba"){
        out(-1);
        return 0;
    }
    if(s.length()<26){
    cout<<s;
    char c='a';
    rep(i,26){
        if(count(all(s),c)==0){
            cout<<c<<endl;
            return 0;
        }
        c++;
    }
    }else if(s.length()==26){
        int n=25,d=0;
        while(1){
            s[n]++;
            if(s[n]>'z'){
                s[n-1]++;
                s.erase(s.begin()+n);
                n--;
            }
            if(s[n]>='a'&&s[n]<='z'&&count(all(s),s[n])==1)break;
        }
        cout<<s<<endl;
    }
}