codeforces Round #347 (Div. 2) C - International Olympiad

思路：从后往前一位一位的模拟，每次判断一下当前枚举的数是否之间枚举过了。或者当前枚举数过小，小于1989.

 #include<cstdio>
 #include<cstring>
 #include<cstdlib>
 #include<iostream>
 #include<queue>
 #include<stack>
 #include<cmath>
 #include<algorithm>
 #include<malloc.h>
 using namespace std;
 #define clc(a,b) memset(a,b,sizeof(a))
 #define inf 0x3f3f3f3f
 const int N=;
 #define LL long long
 const double eps = 1e-;
 const double pi = acos(-);
 // inline int r(){
 //     int x=0,f=1;char ch=getchar();
 //     while(ch>'9'||ch<'0'){if(ch=='-') f=-1;ch=getchar();}
 //     while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
 //     return x*f;
 // }

 int vis[];
 int a[]={,,,,,,,,,};//看成基数数组
 int main(){
     int T;
     scanf("%d",&T);
     char s[];
     while(T--){
         scanf("%s",s);
     int len = strlen(s);
     int bas=s[len-]-'';
     int extra=;
     int index=;
     int total=;
     int cur;
     for(int i=len-;s[i]>=''&&s[i]<='';i--){
         extra+=(s[i]-'')*index;
         index*=;
         int pre=a[bas]/index-;
         bool flag=true;
         while(flag){
             pre++;
             cur=pre*index+extra;
             if(cur<a[bas]){
                 continue;
             }
             flag=false;
             for(int j=;j<total;j++){
                 if(vis[j]==cur){
                     flag=true;
                     break;
                 }
             }
         }
         vis[total++]=cur;
     }
     printf("%d\n",vis[--total]);
     }
     return ;
 }