C :

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

//删去1个数字，使结果最大
void del(char* str)
{
	int i;
	int len = strlen(str);
	for(i=0; i<len-1; ++i)
	{
		if(str[i]<str[i+1])
		{
			strcpy(str+i,str+i+1);
			return ;
		}
	}
	strcpy(str+i,str+i+1);
}

int main()  
{  
	int i,k,n,T;
	char arr[100];
scanf("%d",&T);	
while(T--)
{
  scanf("%d%d",&k,&n);
  sprintf(arr,"%d",k);
	  for(i=0; i<n; ++i)
     del(arr);
  printf("%s\n",arr);
}	
return 0;  
} 

C++ :

#include<stdio.h>
#include<string.h>
int main()
{
     char a[200],b[200];
     int i,j,k,l,m,n;
     scanf("%d",&n);
     for (i=0;i<n;i++)
     {
         scanf("%s %d",a,&m);
         
         l=strlen(a);
         m=l-m;
         int y=0;
         if (m==0) printf("0");
         for (j=0;j<m;j++)
         {
              int x=0;
              char c='-';
              for (k=y;k<l-m+j+1;k++)
                  if (a[k]>c){c=a[k]; x=k;}
                  b[j]=c;
                  y=x+1;
         }
         for (j=0;j<m;j++)
            printf("%c",b[j]);
         printf("\n");
     }
}      

Pascal :

var i,j,k,n,x,z:longint;
    s:string;y:char;
begin
 readln(x);
 for z:=1 to x do
  begin
   read(y);s:='';
   while y<>' ' do
    begin
     s:=s+y;read(y);
    end;
   readln(n);
   while n>0 do
    begin
     i:=1;
     while (i<length(s)) and (s[i]>=s[i+1]) do
      inc(i);
     delete(s,i,1);
     dec(n);
    end;
   while (length(s)>1) and (s[1]='0') do
    delete(s,1,1);
   writeln(s);
  end;
end.