51 lines
1.5 KiB
C
51 lines
1.5 KiB
C
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///=============================================================================
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/// itoa.h - A C++ header to implement itoa()
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/// Created: 11 Feb 2015 5:08:51pm
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/// Author: Jeff-Russ
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///=============================================================================
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#pragma once
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#include <iostream>
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using namespace std;
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// A utility function to reverse a string:
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void reverse(char str[], int length)
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{
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int start = 0;
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int end = length -1;
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while (start < end)
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{ swap(*(str+start), *(str+end));
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start++;
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end--;
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}
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};
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char* itoa(int num, char* str, int base)
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{
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int i = 0;
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bool isNegative = false;
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if (num == 0) // Handle 0 explicitly, otherwise
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{ str[i++] = '0'; // empty string is printed for 0
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str[i] = '\0';
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return str;
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}
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// In standard itoa(), negative
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if (num < 0 && base == 10) // numbers are handled only with
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{ isNegative = true; // base 10. Otherwise numbers
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num = -num; // are considered unsigned.
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}
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while (num != 0)
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{ int rem = num % base; // Process individual digits
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str[i++] = (rem > 9)? (rem-10) + 'a' : rem + '0';
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num = num/base;
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}
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if (isNegative) // If number is negative, append '-'
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str[i++] = '-';
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str[i] = '\0'; // Append string terminator
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reverse(str, i); // Reverse the string
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return str;
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};
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