stablegradients/pie-gem5-bysrc huggingface dataset:
// Original C++ solution (slower):
#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;

}

// Optimized solution to the same problem (faster):
#include <cstdio>

using namespace std;



int main()

{

	char ch;

	bool c=false;

	while((ch=getchar())!='\n')

		if(ch=='C')

			c=true;

		else if(ch=='F' && c)

			return printf("Yes")&0;

	printf("No");

	return 0;

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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;

     

     

 }

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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");

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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;

 }

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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");

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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。

 }

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
/*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;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#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;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<iostream>

using namespace std;

char s[300];

int main()

{

	int i=1,f=0;

	cin>>s;

	for(i=0;i<300;i++)

	{

		if(s[i-1]=='C')

			f=1;

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

		{

			cout<<"Yes";

			return 0;

		}

	}

	cout<<"No";

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<bits/stdc++.h>

using namespace std;

string s;

int main()

{

	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";

					return 0;

				}

			}

		}

	}

	cout<<"No";

	return 0;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<iostream>

using namespace std;

string a;   

bool v[2];



int main() {    

    cin >> a;

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

        if(a[i]=='C') v[0] = 1;

        if(a[i]=='F' && v[0]) {

        	printf("Yes\n");

        	return 0;

		}

    }

    printf("No\n");

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<bits/stdc++.h>

using namespace std;

int main(){

    string a;

    cin>>a;

    int cnt=0;  //用来标记

    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;

}

// Optimized solution to the same problem (faster):
#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");

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<iostream>

#include<cstdio>

#include<string>

using namespace std;

string s;

int l;

int main()

{

    cin>>s;

    l=s.size();

    for(register int i=0;i<l;i++)

    {

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

        {

            for(register int j=i+1;j<l;j++)

            {

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

                {

                    cout<<"Yes";

                    return 0;

                }

            }

        }

    }

    cout<<"No";

    return 0;

}

// Optimized solution to the same problem (faster):
#include<stdio.h>

int main()

{

	char ch[100];int i,j,a,b;

	scanf("%s",&ch);b=-1;a=-1;

	for(i=0;i<=99;i++)

	{

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

		{a = i;

		break;

	

	}

	}



	if(a!=-1&&a<=98)

	{

		for(j=0;j<=99;j++)

		{

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

			{

				b=j;

			

			}

		}

		if(a<b) printf("Yes");

		else printf("No");

	}

	else printf("No");

	return 0;

	

}


// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<iostream>

#include<fstream>

#include<algorithm>

#include<string>

using namespace std;

string st;

int k;

int main()

{

     cin>>st;

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

     {

     	if(st[i]=='C')k=1;

     	if(k==1&&st[i]=='F')

		{

		 	cout<<"Yes";

		 	return 0;

		}

     }

     cout<<"No";

    return 0;

}

// Optimized solution to the same problem (faster):
#include<stdio.h>

int main()

{

	char ch[100];int i,j,a,b;

	scanf("%s",&ch);b=-1;a=-1;

	for(i=0;i<=99;i++)

	{

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

		{a = i;

		break;

	

	}

	}



	if(a!=-1&&a<=98)

	{

		for(j=0;j<=99;j++)

		{

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

			{

				b=j;

			

			}

		}

		if(a<b) printf("Yes");

		else printf("No");

	}

	else printf("No");

	return 0;

	

}


// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<bits/stdc++.h>

using namespace std;

string s;

long long x,y,l;

int main()

{

    getline(cin,s);

    l=s.size();

    x=-1;

    y=-1;

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

    {

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

    	{

    		x=i;

    		break;

    	}

    }

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

    {

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

    	{

    		y=i;

    	}

    }    

    if(x!=-1 && y!=-1 && x<y) cout<<"Yes";

    else cout<<"No";

    return 0;

}


// Optimized solution to the same problem (faster):
#include<stdio.h>

int main()

{

	char ch[100];int i,j,a,b;

	scanf("%s",&ch);b=-1;a=-1;

	for(i=0;i<=99;i++)

	{

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

		{a = i;

		break;

	

	}

	}



	if(a!=-1&&a<=98)

	{

		for(j=0;j<=99;j++)

		{

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

			{

				b=j;

			

			}

		}

		if(a<b) printf("Yes");

		else printf("No");

	}

	else printf("No");

	return 0;

	

}


// Fastest known solution for this problem:
// Original C++ solution (slower):
#include <bits/stdc++.h>

#define fi first

#define se second

#define pii pair<int,int>

#define mp make_pair

#define pb push_back

#define space putchar(' ')

#define enter putchar('\n')

#define eps 1e-10

#define MAXN 100005

//#define ivorysi

using namespace std;

typedef long long int64;

typedef unsigned int u32;

typedef double db;

template<class T>

void read(T &res) {

    res = 0;T f = 1;char c = getchar();

    while(c < '0' || c > '9') {

    if(c == '-') f = -1;

    c = getchar();

    }

    while(c >= '0' && c <= '9') {

    res = res * 10 +c - '0';

    c = getchar();

    }

    res *= f;

}

template<class T>

void out(T x) {

    if(x < 0) {x = -x;putchar('-');}

    if(x >= 10) {

    out(x / 10);

    }

    putchar('0' + x % 10);

}

string s;

void Solve() {

    cin >> s;

    bool f = 0;

    for(int i = s.length() - 1 ; i >= 0 ; --i) {

    if(s[i] == 'F') f = 1;

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

        puts("Yes");return;

    }

    }

    puts("No");

}



int main() {

#ifdef ivorysi

    freopen("f1.in","r",stdin);

#endif

    Solve();

    return 0;

}

// Optimized solution to the same problem (faster):
#include<stdio.h>

int main()

{

	char ch[100];int i,j,a,b;

	scanf("%s",&ch);b=-1;a=-1;

	for(i=0;i<=99;i++)

	{

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

		{a = i;

		break;

	

	}

	}



	if(a!=-1&&a<=98)

	{

		for(j=0;j<=99;j++)

		{

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

			{

				b=j;

			

			}

		}

		if(a<b) printf("Yes");

		else printf("No");

	}

	else printf("No");

	return 0;

	

}


// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<bits/stdc++.h>

using namespace std;

int main()

{

	string s;

	cin>>s;

	int i,l=-1,r=-1;

	for(i=0;i<=s.size()-1;i++)

	{

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

	}

	if(l==-1)

	{

		cout<<"No";

		return 0;

	}

	for(i=l;i<=s.size()-1;i++)

	{

		if(s[i]=='F') r=i;

	}

	if(r==-1) cout<<"No";

	else cout<<"Yes";

	return 0;

}

// Optimized solution to the same problem (faster):
#include<stdio.h>

#include<string.h>

int main()

{char a[101];

scanf("%s",a);

int l=strlen(a);

int i,j;

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

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



	for(j=i+1;j<l;j++)

{

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

		printf("Yes");

	return 0;

	}

	}



}

}



	printf("No");

	return 0;

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#include<iostream>

#include<cstdlib>

#include<cstdio>

#include<cstring>

#include<string>

#include<cmath>

using namespace std;



int main()

{

	int len,i,j;

	char s[105];

	bool ok=false;

	scanf("%s",s);

	len=strlen(s);

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

	{

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

		{

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

			{

				if(s[j]=='F') ok=true;

			}

		}

	}

	if(ok==true) cout<<"Yes"<<endl;

	if(ok==false)cout<<"No"<<endl;

	return 0;

}

// Optimized solution to the same problem (faster):
#include<stdio.h>

#include<string.h>

int main()

{char a[101];

scanf("%s",a);

int l=strlen(a);

int i,j;

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

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



	for(j=i+1;j<l;j++)

{

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

		printf("Yes");

	return 0;

	}

	}



}

}



	printf("No");

	return 0;

}

// Fastest known solution for this problem:
// Original C++ solution (slower):
#include <iostream>

#include <cstdio>

#include <cstring>

#include <string>

#define N 105

using namespace std;

char s[N];

int len;

bool a, b;

int main()

{

	scanf("%s", s);

	len = strlen(s);

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

	{

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

			a = true;

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

			b = true;

		if(a && b)

			break;

	}

	if(a && b)

		printf("Yes");

	else

		printf("No");

	return 0;

}

// Optimized solution to the same problem (faster):
#include<stdio.h>

#include<string.h>

int main()

{char a[101];

scanf("%s",a);

int l=strlen(a);

int i,j;

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

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



	for(j=i+1;j<l;j++)

{

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

		printf("Yes");

	return 0;

	}

	}



}

}



	printf("No");

	return 0;

}

// Fastest known solution for this problem: