求大佬赐教，这段代码bug在哪，找不出来啊

#include<stdio.h>
int n,q,i,j,code[100000],need,output,exchange,result[10000];
int bit[]={1,10,100,1000,10000,100000,1000000,10000000};
int main()
{
    chengji();
    for(i=1;i<=n;i++)
    {
        printf("%d",result[i]);
    }
    return 0;
}
int chengji()
{
    scanf("%d%d",&n,&q);
    for(i=1;i<=n;i++)
        scanf("%d",&code[i]);
    for(j=0;j<=n;j++)
    {
        for(i=0;i<=n-j;i++)
        {
            if(code[i]<code[i+1])
            {
                exchange=code[i];
                code[i]=code[i+1];
                code[i+1]=exchange;
            }
        }
    }
    while(q--)
    {
        scanf("%d%d",&need,&output);
        for(i=1;i<=n;i++)
        if(code[i]%bit[need]==output)
        {
                result[i]=code[i];
        }
        else
        {
            result[i]=-1;
        }
    }
}