#include<stdio.h>
#include<string.h>

#define maxlen 100

struct HP
{
    int len;
    int s[maxlen];
};

void PrintHP(HP x)
{
    for(int i=x.len;i>=1;i--)
        printf("%d",x.s[i]);
    printf("\n");
}

void Str2HP(const char *s, HP &x)
{
    x.len=strlen(s);
    for(int i=1;i<=x.len;i++)
        x.s[i]=s[x.len-i]-'0';
}

void Int2HP(int inte,HP &x)
{
    if(inte==0) { x.len=1; x.s[1]=0; return;};
    for(x.len=0;inte>0;)
    {
        x.s[++x.len]=inte%10;
        inte/=10;
    }
}

void Multi(const HP a,const HP b,HP &c)
{
    int i,j;
    c.len=a.len+b.len;
    for(i=1;i<=c.len;i++) c.s[i]=0;
    for(i=1;i<=a.len;i++) for(j=1;j<=b.len;j++) c.s[i+j-1]+=a.s[i]*b.s[j];
    for(i=1;i<c.len;i++){ c.s[i+1]+=c.s[i]/10; c.s[i]%=10;}
    while(c.s[i]) { c.s[i+1]=c.s[i]/10; c.s[i]%=10; i++;}
    while(i>1 && !c.s[i]) i--; c.len=i;
}

void Plus(const HP a,const HP b,HP &c)
{
    int i; c.s[1]=0;
    for(i=1;i<=a.len || i<=b.len || c.s[i]; i++)
    {
        if(i<=a.len) c.s[i]+=a.s[i];
        if(i<=b.len) c.s[i]+=b.s[i];
        c.s[i+1]=c.s[i]/10; c.s[i]%=10;
    }
    c.len=i-1; if(c.len==0) c.len=1;
}

void Subtract(const HP a,const HP b,HP &c)
{
    for(int i=1,j=0;i<=a.len;i++)
    {
        c.s[i]=a.s[i]-j; if(i<=b.len) c.s[i]-=b.s[i];
        if(c.s[i]<0) { j=1; c.s[i]+=10;} else j=0;
    }
    c.len=a.len; while(c.len>1 && !c.s[c.len]) c.len--;
}

int HPCompare(const HP x,const HP y)
{
    if(x.len>y.len) return 1;
    if(x.len<y.len) return -1;
    int i=x.len;
    while((i>1)&&(x.s[i]==y.s[i])) i--;
    return x.s[i]-y.s[i];
}

void Divide(const HP a,const HP b,HP &c,HP &d)
{
    int i,j; d.len=1; d.s[1]=0;
    for(i=a.len;i>0;i--)
    {
        if(!(d.len==1&&d.s[1]==0))
        {
            for(j=d.len;j>0;j--)
                d.s[j+1]=d.s[j];
            ++d.len;
        }
        d.s[1]=a.s[1]; c.s[i]=0;
        while((j=HPCompare(d,b))>=0)
        {
            Subtract(d,b,d); c.s[i]++;
            if(j==0)
                break;
        }
        c.len=a.len;
        while((c.len>1)&&(c.s[c.len]==0)) c.len--;
    }
}

int main()
{
    HP ans[201];
    Int2HP(1,ans[1]);
    Int2HP(2,ans[2]);
    int i;
    for(i=3;i<=200;i++)
        Plus(ans[i-1],ans[i-2],ans[i]);
    int n;
    while(scanf("%d",&n)!=EOF)
        PrintHP(ans[n]);
    return 0;
}