A simple calculator written in C language

Initial version:

#include <stdio.h>

int Checkpassword ();

int add (int x,int y);

int sub (int x,int y);

int multi (int x,int y);

Float Quo (float x1,float y1);

int com (int x,int y);

int x, y;

int result;

int select;

float RESULT1;

float x1,y1;

int SUCCESS,PSW;

int A;

int i;

int t;

void Main ()

{

printf ("Please enter password: \ n");

i=0;

do{

scanf ("%d", &a);

if (a!=1234 && i<2)

printf ("Please reenter password: \ n");

Else

i=3;

i++;

}while (i<=2);

if (a==1234)

{

for (T=1;t!=6;t=select)

{

printf ("+=============================+\n");

printf ("+====== = = = = = Main = Dish = Single ======+\n");

printf ("+=============================+\n");

printf ("+==========1, Addition ==========+\n");

printf ("+==========2, Subtraction ==========+\n");

printf ("+==========3, multiplication ==========+\n");

printf ("+==========4, Division ==========+\n");

printf ("+==========5, seeking ==========+\n");

printf ("+==========6, Exit ==========+\n");

printf ("+=============================+\n");

printf ("Please enter your choice: \ n");

scanf ("%d", &select);

Switch (SELECT)

{

Case 1:

printf ("Please enter two number: \ n");

scanf ("%d%d", &x,&y);

Result=add (x, y);

printf ("%d+%d=%d\n", X,y,result);

Break

Case 2:

printf ("Please enter two number: \ n");

scanf ("%d%d", &x,&y);

Result=sub (x, y);

printf ("%d-%d=%d\n", X,y,result);

Break

Case 3:

printf ("Please enter two number: \ n");

scanf ("%d%d", &x,&y);

Result=multi (x, y);

printf ("%d*%d=%d\n", X,y,result);

Break

Case 4:

printf ("Please enter two number: \ n");

scanf ("%f%f", &x1,&y1);

Result1=quo (X1,Y1);

printf ("%f/%f=%f\n", X1,Y1,RESULT1);

Break

Case 5:

printf ("Please enter two number: \ n");

scanf ("%d%d", &x,&y);

Result=com (x, y);

printf ("%d/%d=%d\n", X,y,result);

Break

Case 6:

Break

Default

printf ("Please enter the number of" between the numbers \ n ");

Break

}

}

}

}

int add (int x,int y)

{

int sum;

Sum=x+y;

return sum;

}

int sub (int x,int y)

{

int sub;

Sub=x-y;

return sub;

}

int multi (int x,int y)

{

int multi;

Multi=x*y;

return multi;

}

Float Quo (float x,float y)

{

float quo;

quo=x/y;

Return quo;

}

int com (int x,int y)

{

int com;

com=x%y;

return COM;

}

int Checkpassword (int psw)

{

if (psw==1234)

Success=1;

Else

Success=-1;

return success;

}

After the revision:

#include <stdio.h>

int Yanzheng (int);

void Caidan ();

void Jiafa (Int,int);

void Jianfa (Int,int);

void Chengfa (float,float);

void Chufa (float,float);

void Mo (Int,int);

void Main () {

int x,m;

int y;

float A, B;

printf ("Please enter password: \ n");

scanf ("%d", &x);

M=yanzheng (x);

if (m==1) {

Caidan ();

int y;

float A, B;

for (; y!=6;) {

printf ("Please enter option: \ n");

scanf ("%d", &y);

if (y>=1 && y<6) {

printf ("Please enter two numbers to operate: \ n");

scanf ("%f%f", &a,&b);

}

Switch (y) {

Case 1:jiafa (A, b);

Case 2:jianfa (A, b);

Case 3:CHENGFA (A, b);

Case 4:chufa (A, b);

Case 5:mo (A, b);

Case 6:break;

default:printf ("option input Error! Please retry \ n ");

}

}

}

}

int Yanzheng (int x) {

int i,m;

for (i=1,m=0;i<3;i++) {

if (x==1234) {

M=1;

Break

}

printf ("Please re-enter password:");

scanf ("%d", &x);

}

return m;

}

void Caidan () {

printf ("+=============================+\n");

printf ("+====== = = = = = Main = Dish = Single ======+\n");

printf ("+=============================+\n");

printf ("+==========1, Addition ==========+\n");

printf ("+==========2, Subtraction ==========+\n");

printf ("+==========3, multiplication ==========+\n");

printf ("+==========4, Division ==========+\n");

printf ("+==========5, seeking ==========+\n");

printf ("+==========6, Exit ==========+\n");

printf ("+=============================+\n");

}

void Jiafa (int x,int y) {

int sum;

Sum=x+y;

printf ("%d\n", sum);

}

void Jianfa (int x,int y) {

int cha;

Cha=x-y;

printf ("%d\n", cha);

}

void Chengfa (float x,float y) {

float Ji;

Ji=x*y;

printf ("%f\n", Ji);

}

void Chufa (float x,float y) {

float Shang;

shang=x/y;

printf ("%f\n", Shang);

}

void Mo (int x,int y) {

int mo;

mo=x%y;

printf ("%d\n", MO);

}

A simple calculator written in C language