为什么我下载了10，和，500，这两个数据都对了，但是评测九个RE

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

const char* plus(char arr[], char brr[]) {
    long long  crr[1000000];
    long long  drr[1000000];
    long long  err[1000000];
    char grr[1000000] = "0";
    int  sz = strlen(arr);
    int  sz2 = strlen(brr);
    for (int i = 0; i < sz; i++) {
        crr[i] = arr[sz - i - 1] - 48;
    }
    /*printf("%d", crr[0]);*/
    for (int i = 0; i < sz2; i++) {
        drr[i] = brr[sz2 - i - 1] - 48;
    }
    /*printf("%d", drr[0]);*/
    int min = 0;
    int max;
    if (sz < sz2)
        min = sz;
    else
        min = sz2;
    for (int i = 0; i < min; i++) {
        err[i] = crr[i] + drr[i];
    }
    /*printf("%d", err[0]);*/
    if (min == sz) {
        for (int i = min; i < sz2; i++)
            err[i] = drr[i];
        max = sz2;
    }
    else {
        for (int i = min; i < sz; i++) {
            err[i] = crr[i];
            max = sz;
        }
    }
    for (int i = 0; i < max - 1; i++) {
        if (err[i] > 9) {
            err[i + 1] += err[i] / 10;
            err[i] = err[i] % 10;
        }
    }
    /*printf("%d", err[0]);*/
    if (err[max - 1] > 9) {
        err[max] = err[max - 1] / 10;
        err[max - 1] = err[max - 1] % 10;
        for (int i = 0; i <= max; i++)
            grr[i] = err[max - i] + 48;
    /*  printf("%s", grr);*/
        return grr;
    }
    for (int i = 0; i < max; i++)
        grr[i] = err[max - i - 1] + 48;
    /*printf("%s", grr);*/
    return grr;
}

int main() {
    int n;
    scanf("%d", &n);
    char arr[1000000] = "1";
    char brr[1000000] = "2";
    /*printf("%d", strlen(arr));
    printf("%d", strlen(brr));*/

    char crr[1000000] = "0";
    for (int i = 2; i < n; i++) {
        strcpy(crr, plus(arr, brr));
        strcpy(arr, brr);
        strcpy(brr, crr);
    }
    printf("%s", brr);
    return 0;
}