[백준] 1475번 : 방 번호 - C

https://www.acmicpc.net/problem/1475

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

int main() {
    int n;
    scanf("%d",&n);
    int arr[10]={};
    int count=0;
    char k[10];
    sprintf(k,"%d",n);
    for(int i=0;i<strlen(k);i++){
        arr[n%10]++;
        n/=10;
    }
    arr[6]+=arr[9];
    arr[9]=0;
    for(int i=0;i<10;i++){
        int a=0;
        if(i==6){
            if(arr[i]%2==0) a=arr[i]/2;
            else a=(arr[i]/2)+1;
        }
        else a=arr[i];
        if(a>=count) count=a;
    }
    printf("%d",count);
}