C ++ numeric Conversion

1. Convert decimal to n hexadecimal

1 <n <= 9

The conversion function is implemented as follows:

 

// Convert decimal dec to n, and the result is stored in other. other allocates memory externally <br/> void Decimal_to_Other (int dec, char * other, int n) <br/> {<br/> // 1 <n <= 9 <br/> int I = 0; <br/> int dec_copy = dec; <br/> char * tmpArray = new char [64]; <br/> while (dec_copy! = 0) {<br/> tmpArray [I] = dec_copy % n + '0'; <br/> dec_copy/= n; <br/> I ++; <br/>}// the high position of the native string is stored in tmpArray. <br/> // For example, 6. the binary value is saved as tmpArray [0 ~ 2] = {0, 1} <br/> int len = I; // n hexadecimal String Length <br/> for (I = 0; I <len; I ++) {// The tmpArray will be reversed below, exist in other <br/> other [I] = tmpArray [len-i-1]; <br/>}// other [0 ~ 2] = {, 0} This is the result <br/> other [len] = '/0'; <br/> delete [] tmpArray; <br/>}

 

The call is as follows:

CString szNumber; <br/> char * bin = new char [64]; // convert to binary <br/> Decimal_to_Other (m_Decimal, bin, 2 ); <br/> szNumber. format ("% s", bin); <br/> AfxMessageBox (szNumber); </p> <p> char * octal = new char [64]; // convert to octal sequence <br/> Decimal_to_Other (m_Decimal, octal, 8); <br/> szNumber. format ("% s", octal); <br/> AfxMessageBox (szNumber); </p> <p>

 

Ii. Convert decimal to hexadecimal

The conversion function is as follows:

// Hex allocate space externally <br/> void Decimal_to_Hex (int dec, char * hex) <br/>{< br/> int I = 0, flag; <br/> int dec_copy = dec; <br/> char * tmpArray = new char [64]; <br/> while (dec_copy! = 0) {<br/> flag = dec_copy % 16; <br/> switch (flag) {<br/> case 10: <br/> tmpArray [I] = 'a'; <br/> break; <br/> case 11: <br/> tmpArray [I] = 'B '; <br/> break; <br/> case 12: <br/> tmpArray [I] = 'C'; <br/> break; <br/> case 13: <br/> tmpArray [I] = 'D'; <br/> break; <br/> case 14: <br/> tmpArray [I] = 'E '; <br/> break; <br/> case 15: <br/> tmpArray [I] = 'F'; <br/> break; <br/> default: <br/> tmpArray [I] = flag + '0'; <br/> break; <br/>}< br/> dec_copy/= 16; <br/> I ++; <br/>}< br/> int len = I; // n hexadecimal String Length <br/> for (I = 0; I <len; I ++) {<br/> hex [I] = tmpArray [len-i-1]; <br/>}< br/> hex [len] = '/0'; <br/> delete [] tmpArray; <br/>}

 

The call is as follows:

CString szNumber; <br/> char * hex = new char [64]; // convert to hexadecimal format <br/> Decimal_to_Hex (m_Decimal, hex ); <br/> szNumber. format ("% s", hex); <br/> AfxMessageBox (szNumber );

 

 

Iii. Convert binary to decimal

 

Int Binary_to_Decimal (CString szBin) {<br/> int len = szBin. getLength (); // the length of a binary string <br/> char * str = new char [len]; // the length of a string <br/> double result = 0.0; // result </p> <p> strcpy (str, szBin. getBuffer (0); </p> <p> for (int I = 0; I <len; I ++) {<br/> if (str [I] = '1') {<br/> result + = pow (2, len-i-1 ); // calculate the len-I power of 2 and add it to the final result <br/> continue; <br/>}< br/> else if (str [I] = '0 ') {</p> <p >}< br/> else {<br/> AfxMessageBox ("the input binary string is incorrect! "); <Br/> return 0; <br/>}< br/> return (int) result; <br/>}

 

The call is as follows:

CString szBinary = "101101101"; <br/> int decimal; <br/> CString szDecimal; <br/> decimal = Binary_to_Decimal (szBinary); <br/> szDecimal. format ("decimal result % d", decimal); <br/> AfxMessageBox (szDecimal );

 

Iv. Convert octal to decimal

Int Octal_to_Decimal (CString szOct) {<br/> int len = szOct. getLength (); // String Length <br/> char * str = new char [len]; // storage string <br/> double result = 0.0; // result </p> <p> int nOct; <br/> strcpy (str, szOct. getBuffer (0); </p> <p> for (int I = 0; I <len; I ++) {</p> <p> if (str [I] = '0') {<br/> nOct = 0; <br/>}< br/> else if (str [I] = '1') {<br/> nOct = 1; <br/>}< br/> else if (str [I] = '2') {<br/> nOct = 2; <br/>}< br/> else if (str [I] = '3') {<br/> nOct = 3; <br/>}< br/> else if (str [I] = '4 ') {<br/> nOct = 4; <br/>}< br/> else if (str [I] = '5') {<br/> nOct = 5; <br/>}< br/> else if (str [I] = '6') {<br/> nOct = 6; <br/>}< br/> else if (str [I] = '7') {<br/> nOct = 7; <br/>}< br/> else {<br/> AfxMessageBox ("the eight-character string entered is incorrect! "); <Br/> return 0; <br/>}</p> <p> result + = (nOct * pow (8, len-i-1 )); <br/> // CString msg; msg. format ("nOct = % d pow = % f result = % f", nOct, pow (8, len-i-1), result); <br/> // AfxMessageBox (msg ); <br/>}< br/> // delete [] str; <br/> return (int) result; <br/>}

The call is as follows:

CString szOctal = "1721"; <br/> int decimal; <br/> CString szDecimal; <br/> decimal = Octal_to_Decimal (szOctal); <br/> szDecimal. format ("decimal result % d", decimal); <br/> AfxMessageBox (szDecimal );

 

 

5. Convert hexadecimal to decimal

Int Hex_to_Decimal (CString szHex) {<br/> int len = szHex. getLength (); // String Length <br/> char * str = new char [len]; // storage string <br/> double result = 0.0; // result </p> <p> int nHex; <br/> strcpy (str, szHex. getBuffer (0); </p> <p> for (int I = 0; I <len; I ++) {</p> <p> if (str [I] = '0') {<br/> nHex = 0; <br/>}< br/> else if (str [I] = '1') {<br/> nHex = 1; <br/>}< br/> else if (str [I] = '2') {<br/> nHex = 2; <br/>}< br/> else if (str [I] = '3') {<br/> nHex = 3; <br/>}< br/> else if (str [I] = '4 ') {<br/> nHex = 4; <br/>}< br/> else if (str [I] = '5') {<br/> nHex = 5; <br/>}< br/> else if (str [I] = '6') {<br/> nHex = 6; <br/>}< br/> else if (str [I] = '7') {<br/> nHex = 7; <br/>}< br/> else if (str [I] = '8') {<br/> nHex = 8; <br/>}< br/> else if (str [I] = '9') {<br/> nHex = 9; <br/>}< br/> else if (str [I] = 'A') {<br/> nHex = 10; <br/>}< br/> else if (s Tr [I] = 'B') {<br/> nHex = 11; <br/>}< br/> else if (str [I] = 'C') {<br/> nHex = 12; <br/>}< br/> else if (str [I] = 'D') {<br/> nHex = 13; <br/>}< br/> else if (str [I] = 'E') {<br/> nHex = 14; <br/>}< br/> else if (str [I] = 'F') {<br/> nHex = 15; <br/>}< br/> else {<br/> AfxMessageBox ("The hexadecimal string entered is incorrect! "); <Br/> return 0; <br/>}</p> <p> result + = (nHex * pow (16, len-i-1 )); <br/>}< br/> return (int) result; <br/>}

 

The call is as follows:

CString szHex = "1A2B"; <br/> int decimal; <br/> CString szDecimal; <br/> decimal = Hex_to_Decimal (szHex); <br/> szDecimal. format ("decimal result % d", decimal); <br/> AfxMessageBox (szDecimal );

 

6. stack implementation

// Data structure C language version (Yan Weimin) P48 <br/> void conversion (int N) {<br/> InistStack (S ); <br/> scanf ("% d", dec); // read a decimal value from the screen <br/> while (dec! = 0) {// conversion <br/> Push (S, dec % N); <br/> dec/= N; <br/>}< br/> while (! StackEmpty (S) {// display result <br/> Pop (S, e); <br/> printf ("% d", e ); <br/>}< br/>}

 

 

PS: I have implemented a numeric conversion tool. You can download and use it.

Http://download.csdn.net/source/2869264