C :

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

void Add(char *str1,char *str2,char *str3)
{
	int i,j,i1,i2,tmp,carry;
	int len1=strlen(str1),len2=strlen(str2);
	char ch;
	i1=len1-1;
	i2=len2-1;
	j=carry=0;
	for(;i1>=0&&i2>=0;++j,--i1,--i2)
	{
		tmp=str1[i1]-'0'+str2[i2]-'0'+carry;
		carry=tmp/10;
		str3[j]=tmp%10+'0';
	}
	while(i1>=0)
	{
		tmp=str1[i1--]-'0'+carry;
		carry=tmp/10;
		str3[j++]=tmp%10+'0';
	}
	while(i2>=0)
	{
		tmp=str2[i2--]-'0'+carry;
		carry=tmp/10;
		str3[j++]=tmp%10+'0';
	}
	if(carry)
		str3[j++]=carry+'0';
	str3[j]='\0';
	for(i=0,--j;i<j;++i,--j)
	{
		ch=str3[i];
		str3[i]=str3[j];
		str3[j]=ch;
	}
}

int main()
{
	int n,c=0;
	char s1[205],s2[205],r[205];
	scanf("%d",&n);
	while(n--)
	{
		if(c++)
			printf("\n");
		s1[0]='0';
		s1[1]='\0';
		while(scanf("%s",s2),strcmp(s2,"0"))
		{
			Add(s1,s2,r);
			strcpy(s1,r);
		}
		puts(r);
	}
	return 0;
}

C++ :

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

void Add(char *str1,char *str2,char *str3)
{
	int i,j,i1,i2,tmp,carry;
	int len1=strlen(str1),len2=strlen(str2);
	char ch;
	i1=len1-1;
	i2=len2-1;
	j=carry=0;
	for(;i1>=0&&i2>=0;++j,--i1,--i2)
	{
		tmp=str1[i1]-'0'+str2[i2]-'0'+carry;
		carry=tmp/10;
		str3[j]=tmp%10+'0';
	}
	while(i1>=0)
	{
		tmp=str1[i1--]-'0'+carry;
		carry=tmp/10;
		str3[j++]=tmp%10+'0';
	}
	while(i2>=0)
	{
		tmp=str2[i2--]-'0'+carry;
		carry=tmp/10;
		str3[j++]=tmp%10+'0';
	}
	if(carry)
		str3[j++]=carry+'0';
	str3[j]='\0';
	for(i=0,--j;i<j;++i,--j)
	{
		ch=str3[i];
		str3[i]=str3[j];
		str3[j]=ch;
	}
}

int main()
{
	int n,c=0;
	char s1[205],s2[205],r[205];
	scanf("%d",&n);
	while(n--)
	{
		if(c++)
			printf("\n");
		s1[0]='0';
		s1[1]='\0';
		while(scanf("%s",s2),strcmp(s2,"0"))
		{
			Add(s1,s2,r);
			strcpy(s1,r);
		}
		puts(r);
	}
	return 0;
}

Pascal :

type data=array[0..10000] of integer;

var a,b,c:data;
    stb:string;
    i,j,n,lenb:longint;

function  gaojia(a,b:data):data;
   var i,j,len:integer;
       c:data;
   begin
     fillchar(c,sizeof(c),0);
     if a[0]>b[0] then len:=a[0] else len:=b[0];

     for i:=1 to len do
        begin
          c[i]:=c[i]+a[i]+b[i];
          c[i+1]:=c[i+1]+c[i] div 10;
          c[i]:= c[i] mod 10;
     end;
    if c[len+1]>0 then c[0]:=len+1 else c[0]:=len;
    gaojia:=c;
  end;

begin
  readln(n);
  for i:=1 to n do
    begin
      fillchar(a,sizeof(a),0);
      a[0]:=1;a[1]:=0;

      readln(stb);
      while stb<>'0' do
        begin
          lenb:=length(stb);
          b[0]:=lenb;
          for j:=1 to lenb do val(stb[j],b[lenb-j+1]);
          c:=gaojia(a,b);
          a:=c;
          readln(stb);
       end;
     for j:=c[0] downto 1 do  write(c[j]);
     writeln;
     writeln;
  end;
end.

Java :

import java.math.BigInteger;
import java.util.Scanner;

class Main
{
    public static void main(String[] args)
    {
        Scanner cin=new Scanner(System.in);
        while(cin.hasNext())
        {
            int n=cin.nextInt();
            while(n--!=0)
            {
                BigInteger b2=BigInteger.ZERO;
                BigInteger b1;
                while(true)
                {
                    b1=cin.nextBigInteger();
                    if(b1.compareTo(BigInteger.ZERO)==0)
                    {
                        break;
                    }   
                    b2=b2.add(b1);
                }
                System.out.print(b2);
                if(n>0)
                     System.out.println("\n");
                b1=BigInteger.ZERO;
            }
        }
    }
}

Python :

first = True
for t in xrange(input()):
  ans = 0
  while True:
    x = input()
    ans += x
    if x == 0:
      if not first:
        print ''
      first = False
      print ans
      break