"C Language" analog calculator

Tag:c    calculator    

#include  <stdio.h> #include  <stdlib.h>int _add (int a, int b) {     return a + b;} Int _sub (int a, int b) {    return a - b;} Int _mul (int a, int b) {    return a*b;} Int _div (int a, int b) {    if  (b == 0)    &NBSP;&NBSP;{PRINTF ("except digital 0\n");     }    return a / b;} Void menu () {printf ("*************************\n");p rintf ("**** 1.add   2.sub    ****\n ");p rintf (" **** 3.mul   4.div   ****\n ");p rintf (" ********  0.exit *********\n ");p rintf (" *************************\n ");} Int main () {&NBSP;&NBSP;&NBSP;&NBSP;INT&NBSP;INPUT&NBSP;=&NBSP;1;&NBSP;&NBSP;&NBSP;&NBSP;INT&NBSP;NUM1  = 0;    int num2 = 0;    int ret = 0;    while  (input)      {menu ();p rintf ("Please select";: "); scanf ("%d ",  &input);p rintf (" Please enter two integer operands;: "); scanf ("%d% D ",  &num1, &num2);switch  (input) {case 1:ret = _add (num1, num2); Break;case 2:ret = _sub (num1, num2);break;case 3:         ret = _mul (num1, num2); Break;case 4:ret = _div (NUM1,&NBSP;NUM2); Break;case 0:exit (exit_failure); break;default:printf ("Select Error, please re-select. \ n"); printf ("ret = %d\n",  ret);     }return 0;} Alternatively, the enumeration structure (enum) can also be implemented: #include  <stdio.h> #include  <stdlib.h>enum op{exit,add,sub,mul, Div};int _add (int a, int b) {    return a + b;} Int _sub (int a, int b) {    return a - b;} Int _mul (int a, int b) {    return a*b;} Int _div (int a, int b) {    if  (b == 0)    &NBSP;&NBSP;{PRINTF ("except digital 0\n");     }    return a / b;} Void menu () {printf ("*************************\n");p rintf ("**** 1.add   2.sub    ****\n ");p rintf (" **** 3.mul   4.div   ****\n ");p rintf (" ********  0.exit *********\n ");p rintf (" *************************\n ");} Int (*pfun[5]) (Int, int)  = {0, _add, _sub, _mul, _div};int main () {     int input = 1;    int num1 = 0;     int num2 = 0;    int ret = 0;     while  (Input)     {menu ();p rintf ("Please choose;:");scanf ("%d",  &input);p rintf ("Please enter two integer operands;:"); scanf ("%d%d",  &num1, &num2);if  ( INPUT&NBSP;&GT;=&NBSP;1&NBSP;&AMP;&AMP;&NBSP;INPUT&NBSP;&LT;=&NBSP;4) {Ret = pfun[input] (num1,  NUM2);} else if  (input == 0) {exit (exit_failure);} else{printf ("Select Error \ n");} printf ("ret = %d\n",  ret);} return 0;}

This article from "vs LV" blog, declined reprint!

"C Language" analog calculator