{"trustable":true,"sections":[{"title":"","value":{"format":"HTML","content":"\u003cdiv align\u003d\"left\"\u003eDue to the preparation to the wedding you have to fill up M balloons. There are N volunteers and one device for balloons filling up. Device can fill at most one balloon at a time. Each volunteer can continuously operate the device for 1 minute. \u003cbr\u003eVolunteer number i can fill A\u003csub\u003ei\u003c/sub\u003e balloons during one minute and then he or she must have at least B\u003csub\u003ei\u003c/sub\u003e minutes of rest. \u003cbr\u003eYou are to write a program that computes minimal possible time of filling up M balloons. \u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cbr\u003e\u003cb\u003eInput\u003c/b\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003eThere are two integers M and N on the first line (1 \u0026lt;\u003d M \u0026lt;\u003d 100, 1 \u0026lt;\u003d N \u0026lt;\u003d 10). \u003cbr\u003eNext N lines contain two integers each: A\u003csub\u003ei\u003c/sub\u003e and B\u003csub\u003ei\u003c/sub\u003e (0 \u0026lt;\u003d A\u003csub\u003ei\u003c/sub\u003e \u0026lt;\u003d 10, 1 \u0026lt;\u003d B\u003csub\u003ei\u003c/sub\u003e \u0026lt;\u003d 4). \u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cbr\u003e\u003cb\u003eOutput\u003c/b\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003ePrint one integer T - the minimal number of minutes required to filling M balloons. \u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cbr\u003e\u003cb\u003eSample test(s)\u003c/b\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cbr\u003eInput\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cfont face\u003d\"Courier New\"\u003e\u003c/font\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cpre\u003e\u003c/pre\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e10 3 \u003cbr\u003e4 4 \u003cbr\u003e3 4 \u003cbr\u003e2 3 \u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cdiv align\u003d\"left\"\u003e\u003cdiv align\u003d\"left\"\u003e\u003cbr\u003eOutput\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cfont face\u003d\"Courier New\"\u003e\u003c/font\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cpre\u003e\u003c/pre\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e5 \u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cdiv align\u003d\"left\"\u003e\u003cdiv align\u003d\"left\"\u003e\u003cdiv align\u003d\"right\"\u003e \u003c/div\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003cdiv align\u003d\"right\"\u003e \u003c/div\u003e\u003c/div\u003e\u003cdiv align\u003d\"left\"\u003e\u003chr\u003e\u003c/div\u003e\u003ctable align\u003d\"left\" cellspacing\u003d\"7\"\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd\u003eAuthor:\u003c/td\u003e\u003ctd\u003eAndrew V. Lazarev \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd\u003eResource:\u003c/td\u003e\u003ctd\u003eSaratov SU Contest: Golden Fall 2004 \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd\u003eDate:\u003c/td\u003e\u003ctd\u003eOctober 2, 2004 \u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/table\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003c/div\u003e \u003c/div\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e\r\n\u003c/div\u003e"}}]}