https://twitter.com/kim_upsilon/status/429940847434420224

gistfile1.php

<?php

$input = new SplFileObject('php://stdin');

$line = $input->fgets();
list($curKey, $sum) = explode(',', $line);

while (!$input->eof())
{
  $line = $input->fgets();
  list($key, $value) = explode(',', $line);

  if ($key === $curKey)
  {
    $sum += (int)$value;
  }
  else
  {
    printf("%s,%d\n", $curKey, $sum);

    $curKey = $key;
    $sum = (int)$value;
  }
}

printf("%s,%d\n", $curKey, $sum);

gistfile2.cob

       IDENTIFICATION DIVISION.
       PROGRAM-ID. GROUP-TOTAL.
       ENVIRONMENT DIVISION.
       INPUT-OUTPUT SECTION.
       FILE-CONTROL.
         SELECT IN-FILE ASSIGN TO "hoge.txt".
       DATA DIVISION.
       FILE SECTION.
       FD IN-FILE.
       01 IN-REC.
         02 NAME  PIC X(02).
         02       PIC X(01).
         02 VAL   PIC 9(03).
       WORKING-STORAGE SECTION.
       77 EOF     PIC 9(01) VALUE ZERO.
       77 CURNAME PIC X(02).
       77 TOTAL   PIC 9(03).

       01 OUTLINE.
         02 OUT-NAME  PIC X(02).
         02           PIC X(01) VALUE ",".
         02 OUT-VAL   PIC 9(03).
       PROCEDURE DIVISION.
         OPEN INPUT IN-FILE

         READ IN-FILE
         MOVE NAME TO CURNAME
         MOVE VAL TO TOTAL

         PERFORM UNTIL EOF = 1 
           READ IN-FILE
             AT END 
               MOVE 1 TO EOF 
             NOT AT END 
               IF NAME = CURNAME THEN
                 ADD VAL TO TOTAL
               ELSE
                 MOVE CURNAME TO OUT-NAME
                 MOVE TOTAL TO OUT-VAL
                 DISPLAY OUTLINE

                 MOVE NAME TO CURNAME
                 MOVE VAL TO TOTAL
               END-IF
           END-READ
         END-PERFORM

         MOVE CURNAME TO OUT-NAME
         MOVE TOTAL TO OUT-VAL
         DISPLAY OUTLINE

         CLOSE IN-FILE
         STOP RUN.