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.
1 #include<cstdio> 2 #include<cstring> 3 #include<cstdlib> 4 #include<iostream> 5 #include<queue> 6 #include<stack> 7 #include<cmath> 8 #include<algorithm> 9 #include<malloc.h> 10 using namespace std; 11 #define clc(a,b) memset(a,b,sizeof(a)) 12 #define inf 0x3f3f3f3f 13 const int N=10010; 14 #define LL long long 15 const double eps = 1e-5; 16 const double pi = acos(-1); 17 // inline int r(){ 18 // int x=0,f=1;char ch=getchar(); 19 // while(ch>'9'||ch<'0'){if(ch=='-') f=-1;ch=getchar();} 20 // while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();} 21 // return x*f; 22 // } 23 24 int vis[20]; 25 int a[15]={1990,1991,1992,1993,1994,1995,1996,1997,1998,1989};//看成基数数组 26 int main(){ 27 int T; 28 scanf("%d",&T); 29 char s[10]; 30 while(T--){ 31 scanf("%s",s); 32 int len = strlen(s); 33 int bas=s[len-1]-'0'; 34 int extra=0; 35 int index=1; 36 int total=0; 37 int cur; 38 for(int i=len-1;s[i]>='0'&&s[i]<='9';i--){ 39 extra+=(s[i]-'0')*index; 40 index*=10; 41 int pre=a[bas]/index-1; 42 bool flag=true; 43 while(flag){ 44 pre++; 45 cur=pre*index+extra; 46 if(cur<a[bas]){ 47 continue; 48 } 49 flag=false; 50 for(int j=0;j<total;j++){ 51 if(vis[j]==cur){ 52 flag=true; 53 break; 54 } 55 } 56 } 57 vis[total++]=cur; 58 } 59 printf("%d\n",vis[--total]); 60 } 61 return 0; 62 }
