(4.4)--4.4Multi-waysBranchanditsimpleme.pdf

Multi-ways Branch and its implementationMulti-ways Branch and its implementation4.4In fact,there are someproblems with more than twopossible solutions,which are themulti-waysbranchproblems.For this kind of problem,youcan directly use the if or if.elsestatements to solve the problemsthrough multiple judgments.However：The programwill be less readable and error-prone because of too many levelsof nesting when using if.elsestatements to deal with multi-branchproblems.C+alsoprovides the switch statement forthis kind of problem.Multi-ways Branch and its implementation4.4The form of the switch statement is：switch()case:break;case:break;case:break;default:Multi-ways Branch and its implementation4.4testtestconditionconditionconstant constant expressionexpression1 1constant constant expressionexpression2 2 constant constant expressionNexpressionNdefaultdefaultbranch statementbranch statement1 1branch statementbranch statement2 2branch statement Nbranch statement Nbranch statement branch statement N N+1 1 Flow chart of the switch statement without break statementMulti-ways Branch and its implementation4.4test conditiontest conditionConstant Constant expressionexpression2 2defaultdefaultBranch statementBranch statement1 1 Branch statementBranch statement2 2Branch statementNBranch statementNBranch statementNBranch statementN+1 1Constant Constant expressionNexpressionNConstant Constant expressionexpression1 1Flow chart of the switch statement with break statementMulti-ways Branch and its implementation4.4E.g.1Write a program to output the corresponding ASCII code when the user enters a numeric character(09).The algorithm analysis:If the user inputs 0,then the output is 48;If the user inputs 1,then the output is 49;This multi-branch situation is most suitable for using the switch statement.Multi-ways Branch and its implementation4.4int main()char ch;cout“Please input a numeric character(09):ch;switch(ch)case 0:cout“The ASCII code is48endl;break;case 1:cout The ASCII code is 49endl;break;Multi-ways Branch and its implementation4.4case 2:cout The ASCII code is 50endl;break;case 8:cout The ASCII code is 56endl;break;case 9:cout The ASCII code is 57endl;break;default:cout What you entered is not a numeric character.endl;return 0;