高精度加法模板

只想说这个模板好啊

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
using namespace std;
char s[205][200];
void add(char a[],char b[],char back[])
{
    int i,j,k,up,x,y,z,l;
    char *c;
    if (strlen(a)>strlen(b)) l=strlen(a)+2; else l=strlen(b)+2;
          c=(char *) malloc(l*sizeof(char));
    i=strlen(a)-1;
    j=strlen(b)-1;
    k=0;up=0;
    while(i>=0||j>=0)
    {
        if(i<0) x='0'; else x=a[i];
        if(j<0) y='0'; else y=b[j];
        z=x-'0'+y-'0';
        if(up) z+=1;
        if(z>9) {up=1;z%=10;} else up=0;
        c[k++]=z+'0';
        i--;j--;
    }
    if(up) c[k++]='1';
    i=0;
    c[k]='';
    for(k-=1;k>=0;k--)
    back[i++]=c[k];
    back[i]='';
}
void pre(){
    strcpy(s[1],"1");
    strcpy(s[2],"2");
    //s[2][] = "2";
    for(int i = 3; i<=201; i++)
    {
        add(s[i-1],s[i-2],s[i]);
    }
}
int main()
{
    pre();
    int n;
    while(scanf("%d",&n)!=EOF){
        if(n == 0) printf("
");
        else printf("%s
",s[n]);
    }
    return 0;
}