coderforce 540A Combination Lock

题意：给你两串数字，每次可以改变一位，实现+1，-1操作，且9+1=0&&0-1=9。求最少多少步，才能使s1变到s2.

#include<stdio.h>#include<string.h>#include<math.h>#include<algorithm>using namespace std;const int maxm=1e4+10;char s1[maxm];char s2[maxm];int main(){    int n;    while(scanf("%d",&n)!=EOF)    {        scanf("%s%s",s1,s2);        int cnt=0;        for(int i=0;i<n;i++)        {            int x=s1[i]-'0';            int y=s2[i]-'0';            int step=min((min(x,y)+10-max(x,y)),max(x,y)-min(x,y));            cnt+=step;        }        printf("%d\n",cnt);    }    return 0;}