Savitch
Problem Solving w/ C++, 10e Instructor’s Resource Guide
Chapter 5
//Postcondition:
//Prompt given to the user for input in the format FF II, //where FF is integer number of feet and II is a double //number of inches. feet and inches are returned as entered //by the user.
void convert (int feet, double inches, double& meters ); //Preconditions:
//REQUIRED CONSTANTS: INCHES_PER_FOOT, METERS_PER_FOOT //inches < 12, feet within range of values for int type //Postconditions:
//meters assigned 0.3048 * (feet + inches/12) //observe that the centimeter requirement is met by
//the value of the first two decimal places of the converted //feet, inches input.
void output( int feet, double inches, double meters ); //input: the formal argument for meters fits into a double //output:
//\//\
//where meters is displayed as a number with two decimal //places
int main() {
int feet;
double inches, meters; char ans;
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Copyright ? 2018 Pearson Education, Inc.
Savitch
Problem Solving w/ C++, 10e Instructor’s Resource Guide
Chapter 5
do {
input ( feet, inches );
convert ( feet, inches, meters ); output ( feet, inches, meters );
cout << \ << endl; cin >> ans;
} while ( 'Y' == ans || 'y' == ans );
return 0; }
void input ( int& feet, double& inches ) {
cout << \cin >> feet;
cout << \cin >> inches; }
const double METERS_PER_FOOT = 0.3048; const double INCHES_PER_FOOT = 12.0;
void convert (int feet, double inches, double& meters ) {
meters = METERS_PER_FOOT * (feet + inches/INCHES_PER_FOOT); }
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Copyright ? 2018 Pearson Education, Inc.
Savitch
Problem Solving w/ C++, 10e Instructor’s Resource Guide
Chapter 5
void output( int feet, double inches, double meters ) {
//inches, meters displayed as a number with two decimal //places
cout.setf( ios::showpoint ); cout.setf( ios::fixed ); cout.precision(2);
cout << \ << inches << endl
<< \ << meters << endl; } /*
A typical run follows: 06:59:16:~/AW$ a.out
Enter feet as an integer: 5 Enter inches as a double: 7 the value of feet, inches5,7.00
converted to meters, centimeters is 1.70 Y or y continues, any other character quits y
Enter feet as an integer: 245 Enter inches as a double: 0 the value of feet, inches245,0.00
converted to meters, centimeters is 74.68 Y or y continues, any other character quits q
06:59:49:~/AW$
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Copyright ? 2018 Pearson Education, Inc.
Savitch
Problem Solving w/ C++, 10e Instructor’s Resource Guide
Chapter 5
*/
Practice Program 3: Conversion metric to English Conversion of meters back to feet and inches
//Task: Convert meters with centimeters (just the decimal //part of meters)to feet/inches //
//Input: a length in feet and inches, with possible decimal //part of inches
//Output: A length measured in feet with any decimal fraction //converted to inches by multiplying by 12. Fractions of an //inch are represented by 2 decimal places. //
//Required: functions for input, computation, and output. //Include a loop to repeat the calculation at the user's //option. //
//Remark: The computation is a simple conversion from meters //to feet, inches, where inches has a decimal part. //Output is restricted to 2 decimal places
//Comment: Please see Problem 4 for discussion of 'meters and //centimeters' #include
void input ( double & meters ); //Precondition: function is called //Postcondition:
//Prompt given to the user for input of a number of meters as
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Copyright ? 2018 Pearson Education, Inc.
Savitch
Problem Solving w/ C++, 10e Instructor’s Resource Guide
Chapter 5
//a double. input of a double for meters has been accepted
void convert (int& feet, double& inches, double meters ); //Preconditions:
// REQUIRED CONSTANTS: INCHES_PER_FOOT, METERS_PER_FOOT //Postconditions:
//feet is assigned the integer part of meters (after //conversion to feet units) inches is assigned the
//fractional part of feet ( after conversion to inch units
void output( int feet, double inches, double meters ); //input: the formal argument for meters fits into a double //output:
//\//\//
//where meters is displayed as a number with two decimal //places
int main() {
int feet;
double inches, meters; char ans; do {
input ( meters );
convert ( feet, inches, meters ); output ( feet, inches, meters );
cout << \
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Copyright ? 2018 Pearson Education, Inc.
用C++解决问题第十版Chapter 5 Functions for All Subtasks
