Typically,theproblemstatementhasplentyofwords;yourgoal istoturnthemintoa program. Here isanexample:

Triangle

(Sampleproblem)

Atrianglehasthreesides,eachofwhichhasalength. Itturnsoutthatspecifyingthreenumbers forthelengthofthethreesidesofatriangleisenoughinformationtodrawatriangle.congruentto theoriginalone. However,noteverychoiceofthreenumberscanformatriangle. Forexample,if thenumbersare1.0,2.0,and4.0,thereisnowaytodrawatriangle,becausenoamountof stretchingwillpermitthe1.0and2.0sidestoconnectthetwoendpointsofthe4.0line. The

restrictiononlengthswhichcanformatriangleiscalledtheTiianglelnequaJjty:

a+b>c

wherea,b,andcarethelengthsofthethreesides,cbeing thelongest.

Foreachiterationoftheproblem,youaregiventhreenumbers,andyoumustprintoutalinewith thewordTRIANGLE iftheycanformthesidesofatriangle,andNOiftheycannot. Thereare

threeiterations,thatis, threesetsofthreenumbers. Youwillproducethree linesofoutput.

SampleInput:

1.02.04

454545.0

601580

SampleOutput: NO

TRIANGLE NO

Hereisasamplesolution,codedintheClanguage.Iusedscanfforinput. Theinputisprettyugly,but therestoftheprogramisn'ttoodifficult.

/*Triangleproblem-- C version*/

#include<stdio.h

intmain(){

floata,b,c,t;

inti;

/*repeat 3 times*/

for(i=O;i<3; i++){

if (scanf("%g",&a) !=1){printf("oops!badinput?\n");} if (scanf("%g",&b) != 1){printf("oops!badinput?\n");} if (scanf("%g",&c) != 1){printf("oops!badinput?\n");}

/*make sureclongest side */

if (a>c){

floatt= c;

c= a;

a =t;

}

if(b>c){

floattc;

c =b;

b=t;

}

/*triangleinequalitysatisfied? */

if(a+bc){

printf("TRIANGLE\n");

}

else{

printf("NO\n");

}

}

}

ThissamplesolutioniscodedinC++. MuchprettierVOthanC:

IITriangleproblem--C++version

#include<iostream>

main(){

IIdothethreetrialscalledforinthecontest for(inti=0; i<3;i++){

floata,b,c;

cina>b>Ci

IImakesureclongestside

if(a>c){

floatt= Cj

c= a;

a= t;

}

if(b>c){

floattc;

cb·I

b= t·I

}

IItriangleinequalitysatisfied?

if(a+b>c){

cout11 TRIANGLE\n11 ;

}

else{

cout"NO\n";

}

}IIendofrepeat3timesloop

}IIendofmain

IITriangleproblem--Javaversion importjava.util.Scanner;

publicclassSample{

publicstaticvoidmain(String[]unused){

IIsetupforinputfromconsole

Scannerins=newScanner(System.in);IINOTICEthescanneris

createdOUTSIDEtheloop!

IIdothethreetrialscalledforinthecontest

for(inti=0;i<3;i++){

floata1 b1c;

IIreadthethreenumbers ains.nextFloat();

b=ins.nextFloat();

c=ins.nextFloat();

II makesureclongestside if(a>c){

floatt=c;

ca·I

at·I

}

if(b>C){

floattc·I

cb·I

b=t;

}

IItriangleinequalitysatisfied?

if(a+bc){

System.out.println("TRIANGLE");

}

else{ System.out.println("NO");

}

}IIendofrepeat3timesloop

}IIendofmain

}II endofSampleclass

ThisexampleiscodedinVisualBasic.NoticetheuseofCDbl(String)toconverta Stringinputtoadouble;ingeneral,youneedtopaymoreattentiontoinputthanyou maybeusedto.

ModuleModule!

DimxAsString Dimy()AsString DimsAsDouble

Dima,b,cAsDouble

SubMain()

ForiAsInteger=1To3

'funnyinputwithmultipleitemsperline x=Console.Readline

y=x.Split

'IassumeIknowwhatitlookslike...a=CDbl(y(O))

b=CDbl(y(l))

c=CDbl(y(2))

'triangletestcode:

' firstputlargestvalueina

IfabThen

s =a a= b b=s

EndIf

IfacThen

s=a

a=c

c=s

EndIf

'commented outdebuggingcode

'Console.Writeline(a)

'Console.Writeline(b)

'Console.Writeline(c)

'maincomparisonofprogram

Ifa>=b+cThen

Console.Writeline(..NOTATRIANGLE..)

Else.

Console.Writeline(..TRIANGLE11

EndIf

Next

Iinsteadoffinalreadline,whichwouldconfusethejudges,

IIinsteadplaceaVSbreakpoint ontheEndSub

EndSub

EndModule

.#Thisisasampleprogramusingpython3.2,whichdiffersfrompython2.x

#insomesimpleways:

#1)printisafunction,andmusthaveparenteseslikeanyotherfuctioncall

#2)thepreferredwaytoacceptinputfromtheconsoleis"input()"

#whichalwaysreturnsastring.Youmayuse

#int(input())orfloat(input())ifyouwantaninteger

#orfloating-pointvalue.

#Thisprogramdoesthreeiterationsofthetriangleinequalityprogram

#foreachiteration,itacceptsthreenumbers,anddetermineswhetherthey

#canformatriangle

foriinrange(3):

#theinputforthe'sampleprogramiseasyinC++,orwithajavaScanner,

#butabitofapainforPython line=1 1 #lineinitiallyempty

items=list()#startitemsasemptylist while(len(items)3):

line=line+1 1 +input()#acceptawholelineofinput

items=line.split()#splitonwhitespaceintoanarrayofitems a=float(items[O])

bfloat(items[l])

c=float(items[2])

ifa<b+candbateandca+b print("triangle")

else:

print("no")