stablegradients/pie-gem5-pairs huggingface dataset:
// Slower C++ solution:
#include<iostream>

#include<cstdio>

#include<string>

using namespace std;

 int q,p,w[1000001],u[1000001],o;

 string a;

 int main()

 {

     cin>>a;

     for (int i=0;i<a.size();i++)

     {

         if (a[i]=='C') 

         {

             p++;

             u[p]=i+1;

         }

         else if (a[i]=='F')

         {

            q++;

             w[q]=i+1;

         }

     }

     if (q>=1 && p>=1)

     {

     for (int i=1;i<=p;i++)

     {

         for (int j=1;j<=q;j++)

         {

             if (u[i]<w[j])

             {

                 o=1;

             }

         }

     }

     if (o==1) cout<<"Yes"<<endl;

     else cout<<"No"<<endl;  

     }

     else cout<<"No"<<endl;

 }

// Faster C++ solution for the same problem (measured speedup: 5.324330879244645x):
#include<cstdio>

#include<cstring>

char a[1000];

bool c;

int main()

{

	scanf("%s",a);

	for(int i=0;i<strlen(a);++i)

	{

		if(!c)

		{

			if(a[i]=='C')	c=1;

		}

		else

		{

			if(a[i]=='F')

			{

				printf("Yes\n");

				return 0;

			}

		}

	}

	printf("No\n");

	return 0;

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int q,p,w[1000001],u[1000001],o;

string a;

int main()

{

    cin>>a;

    for(int i=0;i<a.size();i++)

    {

        if(a[i]=='C') 

        {

            p++;

            u[p]=i+1;

        }

        else if (a[i]=='F')

        {

            q++;

            w[q]=i+1;

        }

    }

    if (q>=1 && p>=1)

    {

    for (int i=1;i<=p;i++)

    {

        for (int j=1;j<=q;j++)

        {

            if (u[i]<w[j])

            {

                o=1;

            }

        }

    }

    if (o==1) cout<<"Yes"<<endl;

    else cout<<"No"<<endl; 

    }

    else cout<<"No"<<endl;

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.323974898291874x):
#include<cstdio>

#include<cstring>

char a[1000];

bool c;

int main()

{

	scanf("%s",a);

	for(int i=0;i<strlen(a);++i)

	{

		if(!c)

		{

			if(a[i]=='C')	c=1;

		}

		else

		{

			if(a[i]=='F')

			{

				printf("Yes\n");

				return 0;

			}

		}

	}

	printf("No\n");

	return 0;

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int n;

string s;

int main(void)

{

    cin>>s;

    n=s.size();

    for(int i=0;i<n;i++)

    {

        if(s[i]=='C')

        {

            for(int j=i+1;j<n;j++)

            {

                if(s[j]=='F')

                {

                    printf("Yes");

                    exit(0);

                }

            }

        }

    }

    printf("No");

}

// Faster C++ solution for the same problem (measured speedup: 5.2988522822312065x):
#include<cstdio>

#include<cstring>

char a[1000];

bool c;

int main()

{

	scanf("%s",a);

	for(int i=0;i<strlen(a);++i)

	{

		if(!c)

		{

			if(a[i]=='C')	c=1;

		}

		else

		{

			if(a[i]=='F')

			{

				printf("Yes\n");

				return 0;

			}

		}

	}

	printf("No\n");

	return 0;

}
// Slower C++ solution:
#include<iostream>

#include<cstdio>

#include<string>

using namespace std;

 int q,p,w[1000001],u[1000001],o;

 string a;

 int main()

 {

     cin>>a;//首先输入字符串

     for (int i=0;i<a.size();i++)//从0位开始循环

     {

         if (a[i]=='C') 

         {

             p++;

             u[p]=i+1;

         }//判断是否发现C这个东西，并统计其位置

         else if (a[i]=='F')

         {

            q++;

             w[q]=i+1;

         }

     }//判断是否发现F，同理 统计位置情况

     if (q>=1 && p>=1)

     {

     for (int i=1;i<=p;i++)

     {

         for (int j=1;j<=q;j++)

         {

             if (u[i]<w[j])

             {

                 o=1;

             }

         }

     }//循环，找到C是否在F的前面

     if (o==1) cout<<"Yes"<<endl;//在前面则Yes

     else cout<<"No"<<endl;//否则No   

     }

     else cout<<"No"<<endl;//不存在两个数，直接No

     //以上为全部过程，希望能理解。

 }

// Faster C++ solution for the same problem (measured speedup: 5.324330879244645x):
#include<cstdio>

#include<cstring>

char a[1000];

bool c;

int main()

{

	scanf("%s",a);

	for(int i=0;i<strlen(a);++i)

	{

		if(!c)

		{

			if(a[i]=='C')	c=1;

		}

		else

		{

			if(a[i]=='F')

			{

				printf("Yes\n");

				return 0;

			}

		}

	}

	printf("No\n");

	return 0;

}
// Slower C++ solution:
/*https://www.luogu.org/problemnew/show/AT2084*/

/*testing*/

#include<bits/stdc++.h>

using namespace std;

char ch[100]; bool b,ans;

int main(void){

	scanf("%s",ch);

	for(int i=0;ch[i]!=0;i++){

		if(ch[i]=='C') b=true;

		if(b&&ch[i]=='F') ans=true;

	}

	printf(ans?"Yes\n":"No\n");

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.260695199345454x):
#include<cstdio>

#include<cstring>

char a[1000];

bool c;

int main()

{

	scanf("%s",a);

	for(int i=0;i<strlen(a);++i)

	{

		if(!c)

		{

			if(a[i]=='C')	c=1;

		}

		else

		{

			if(a[i]=='F')

			{

				printf("Yes\n");

				return 0;

			}

		}

	}

	printf("No\n");

	return 0;

}
// Slower C++ solution:
#include <iostream>

#include <cstdio>

#include <algorithm>

#include <cstring>

#define Js for(int i=0;i<Len;i++) {

#define is if(c[i]=='C') p=1;

#define a if(c[i]=='F' && p==1) q=1;}

#define sha if(p&&q) cout<<"Yes\n"<<endl; else cout<<"No\n";

#define bi return 0;}

using namespace std;

char c[105];

int main() {

    scanf("%s",c);

    int p=0,q=0;

    int Len=strlen(c);

    Js is a sha bi

// Faster C++ solution for the same problem (measured speedup: 5.314123639500519x):
#include<cstdio>

#include<cstring>

char a[1000];

bool c;

int main()

{

	scanf("%s",a);

	for(int i=0;i<strlen(a);++i)

	{

		if(!c)

		{

			if(a[i]=='C')	c=1;

		}

		else

		{

			if(a[i]=='F')

			{

				printf("Yes\n");

				return 0;

			}

		}

	}

	printf("No\n");

	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main()

{

	string a;

	int s=1000,b=0;

	cin>>a;

	for(int i=0;i<a.size();i++)

	{

		if(a[i]=='C')

{

if(i<s)

{

s=i;

}

}

		if(a[i]=='F')

{

if(i>b)

{

b=i;

}

}

	}

	if(s<b)

	{

		cout<<"Yes\n";

	}

	else

	{

		cout<<"No\n";

	}

return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.307374945901615x):
#include<cstdio>

#include<cstring>

char a[1000];

bool c;

int main()

{

	scanf("%s",a);

	for(int i=0;i<strlen(a);++i)

	{

		if(!c)

		{

			if(a[i]=='C')	c=1;

		}

		else

		{

			if(a[i]=='F')

			{

				printf("Yes\n");

				return 0;

			}

		}

	}

	printf("No\n");

	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main(){

    string s;

	int a=0;

    cin>>s;

    for(int i=0;s[i]!='\0';++i){

    	if(s[i]=='C'){

    		a=1;

		}

		if(a==1){

			if(s[i]=='F'){

				cout<<"Yes";

				return 0;

			}

		}

	}

	cout<<"No";

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.320876269129831x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int main()

{

	int len,i,ok=0;

	string s;

	cin>>s;

	len=s.size()-1;

	for(i=0;i<=len;i++)

	{

		if(ok==0&&s[i]=='C')

		ok=1;

		if(ok==1&&s[i]=='F')

		ok=2;

		if(ok==2)

		break;

	}

	if(ok==2)

	cout<<"Yes";

	else

	cout<<"No";

}

// Faster C++ solution for the same problem (measured speedup: 5.3640492001686555x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<iostream>

#include<cstring>

using namespace std;

int main(){

	string s;

	getline(cin,s);

	if(s.find("C")<s.length()){

		int k=s.find("C");

		if(s.find("F",k)<s.length()) cout<<"Yes";

		else cout<<"No";

	}

	else cout<<"No";

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.363184356830446x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<iostream>

#include<cstdio>

#include<cstring>

using namespace std;

int main(){

    string s;

    cin>>s;

    for(int i=0;i<s.size();i++){

        if(s[i]=='C'){

            for(int j=i+1;j<s.size();j++){

                if(s[j]=='F'){

                    cout<<"Yes"<<endl;

                    return 0;

                }

            }

        }

    }

    cout<<"No"<<endl;

    return 0;

    

}

// Faster C++ solution for the same problem (measured speedup: 5.333244668391292x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h> 

using namespace std;

char a[1000];

int main()

{

cin>>a;

for(int i=0;i<strlen(a);i++)

{

	if (a[i]=='C') 

	 {

	 	for(int ii=i+1;ii<strlen(a);ii++)

	 	 {

	 	 	if (a[ii]=='F') {cout<<"Yes"<<endl;return 0;}

	 	 }

	 }

}

cout<<"No"<<endl;

return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.336836218007654x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>

#include<string>

using namespace std;

int main()

{

	string n;

	int a,m;

	cin>>n;

	a=n.size();

	for(int i=0;i<a;i++)

	{

		if(n[i]=='C')

		{

			for(int k=i+1;k<=a-1;k++)

			{

				if(n[k]=='F')

				{

					cout<<"Yes"<<endl;

					return 0;

				}

			}

		}

	}

	cout<<"No"<<endl;

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.377985101869506x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int main()

{

	bool a=0;

	string b;

	cin>>b;

	for(int i=0;i<b.length();i++)

	{

		if(b[i]=='C')

			a=1;

		if(b[i]=='F'&&a)

		{

			printf("Yes\n");

			return 0;

		}

	}

	printf("No\n");

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.3107798321754744x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main(){

    char c;

    bool fc=0;

    while(cin>>c){

        if(c=='C'&&!fc)

            fc=1;

        if(c=='F'&&fc){

            cout<<"Yes"<<endl;

            return 0;

        }

    }

    cout<<"No"<<endl;

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.335103722135443x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>



using namespace std;



int main()

{

    string a;

    cin >> a;

    int cnt=0;  

    for(int i=0;i<a.size();i++)

    {

        if(a[i]=='C')

            cnt=1;   

        if(a[i]=='F'&&cnt==1)

        {

            cout << "Yes";

            return 0;

        }

    }

    cout << "No";

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.365077942073634x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

string s;

int main()

{

    cin>>s;

    int len=s.length();

    for(int i=0;i<len;i++)

    {

        if(s[i]=='C')

        {

            for(int j=i + 1;j<len;j++)

            {

                if(s[j]=='F')

                {

                    cout<<"Yes"<<endl; 

                    return 0;

                }

            }

        }

    }

    cout<<"No"<<endl;

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.337605390221498x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int main(){

	int flag=0;

	string s;

	cin>>s;

	for(int i=0;i<s.length();i++){

		if(flag==0&&s[i]=='C'){

			flag++;

			continue;

		}

		if(flag==1&&s[i]=='F'){

			cout<<"Yes";

			return 0;

		}

	}

	cout<<"No";

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.321368569887691x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<iostream>

#include<cstdio>

#include<string>

using namespace std;

 int q,p,w[1000001],u[1000001],o;

 string a;

 int main()

 {

     cin>>a;

     for (int i=0;i<a.size();i++)

     {

         if (a[i]=='C') 

         {

             p++;

             u[p]=i+1;

         }

         else if (a[i]=='F')

         {

            q++;

             w[q]=i+1;

         }

     }

     if (q>=1 && p>=1)

     {

     for (int i=1;i<=p;i++)

     {

         for (int j=1;j<=q;j++)

         {

             if (u[i]<w[j])

             {

                 o=1;

             }

         }

     }

	 if (o==1) cout<<"Yes"<<endl;

     else cout<<"No"<<endl;	

     }

     else cout<<"No"<<endl;

     

     

 }

// Faster C++ solution for the same problem (measured speedup: 5.337824320213515x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

char ch[110];

int n;

int main(){

	cin>>ch;

	n=strlen(ch);

	for(int i=0;i<n;i++){

		if(ch[i]=='C'){

			for(int j=i+1;j<n;j++){

				if(ch[j]=='F'){

					printf("Yes");

					return 0;

				};

			}

			printf("No");

			return 0;

		}

	}

	printf("No");

}

// Faster C++ solution for the same problem (measured speedup: 5.31304283386831x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<iostream>

#include<cstdio>

#include<string>

using namespace std;

 int q,p,w[1000001],u[1000001],o;

 string a;

 int main()

 {

     cin>>a;

     for (int i=0;i<a.size();i++)

     {

         if (a[i]=='C') 

         {

             p++;

             u[p]=i+1;

         }

         else if (a[i]=='F')

         {

            q++;

             w[q]=i+1;

         }

     }

     if (q>=1 && p>=1)

     {

     for (int i=1;i<=p;i++)

     {

         for (int j=1;j<=q;j++)

         {

             if (u[i]<w[j])

             {

                 o=1;

             }

         }

     }

     if (o==1) cout<<"Yes"<<endl;

     else cout<<"No"<<endl;  

     }

     else cout<<"No"<<endl;

 }

// Faster C++ solution for the same problem (measured speedup: 5.337824320213515x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int q,p,w[1000001],u[1000001],o;

string a;

int main()

{

    cin>>a;

    for(int i=0;i<a.size();i++)

    {

        if(a[i]=='C') 

        {

            p++;

            u[p]=i+1;

        }

        else if (a[i]=='F')

        {

            q++;

            w[q]=i+1;

        }

    }

    if (q>=1 && p>=1)

    {

    for (int i=1;i<=p;i++)

    {

        for (int j=1;j<=q;j++)

        {

            if (u[i]<w[j])

            {

                o=1;

            }

        }

    }

    if (o==1) cout<<"Yes"<<endl;

    else cout<<"No"<<endl; 

    }

    else cout<<"No"<<endl;

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.337467437098937x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int n;

string s;

int main(void)

{

    cin>>s;

    n=s.size();

    for(int i=0;i<n;i++)

    {

        if(s[i]=='C')

        {

            for(int j=i+1;j<n;j++)

            {

                if(s[j]=='F')

                {

                    printf("Yes");

                    exit(0);

                }

            }

        }

    }

    printf("No");

}

// Faster C++ solution for the same problem (measured speedup: 5.312281152843243x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
#include<iostream>

#include<cstdio>

#include<string>

using namespace std;

 int q,p,w[1000001],u[1000001],o;

 string a;

 int main()

 {

     cin>>a;//首先输入字符串

     for (int i=0;i<a.size();i++)//从0位开始循环

     {

         if (a[i]=='C') 

         {

             p++;

             u[p]=i+1;

         }//判断是否发现C这个东西，并统计其位置

         else if (a[i]=='F')

         {

            q++;

             w[q]=i+1;

         }

     }//判断是否发现F，同理 统计位置情况

     if (q>=1 && p>=1)

     {

     for (int i=1;i<=p;i++)

     {

         for (int j=1;j<=q;j++)

         {

             if (u[i]<w[j])

             {

                 o=1;

             }

         }

     }//循环，找到C是否在F的前面

     if (o==1) cout<<"Yes"<<endl;//在前面则Yes

     else cout<<"No"<<endl;//否则No   

     }

     else cout<<"No"<<endl;//不存在两个数，直接No

     //以上为全部过程，希望能理解。

 }

// Faster C++ solution for the same problem (measured speedup: 5.337824320213515x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}
// Slower C++ solution:
/*https://www.luogu.org/problemnew/show/AT2084*/

/*testing*/

#include<bits/stdc++.h>

using namespace std;

char ch[100]; bool b,ans;

int main(void){

	scanf("%s",ch);

	for(int i=0;ch[i]!=0;i++){

		if(ch[i]=='C') b=true;

		if(b&&ch[i]=='F') ans=true;

	}

	printf(ans?"Yes\n":"No\n");

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.274027368539577x):
#include<cstdio>

#include <cstring>

using namespace std;

char ch[1000000],l,r;

int a;



int main(){

    scanf("%s",ch);

    a=strlen(ch);

    for(int i=0;i<a;i++){

        if(l==0){

            if(ch[i]=='C'){

                l=1;

            }

        }

        else{

            if(ch[i]=='F'){

                printf("Yes");

                return 0;

            }

        }

    }

    printf("No");

}