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#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
/*
* Helper function that retrieves numbers 'bit' value
* ie: 1's 31st bit is 1
*/
int getNthBit(uint32_t number, int bit) {
if (bit <0 || bit >= 32) {
printf("Bit %d is invalid\n", bit);
exit (EXIT_FAILURE);
}
return (number & (1<<bit)) != 0;
}
/*
*
* This function takes in two arrays: nums (of length nNums), and
* bits (of length nBits). This function should:
*
* - Check that there is enough space in bits to hold all the bits
* of "nums". Note that each number in "nums" will results in 32
* bits in "bits". If this is not true, your function should
* print a message with the format:
* "Invalid call to numToBits! nBits is %d, nNums is %d\n",
* (where the first %d is nBits, and the second %d is nNums)
* then return without doing anything else.
*
* - Put the individual bits of each number into the "bits" array.
* The bits put into this array should be ordered so that the first
* 32 bits represent nums[0], the next 32 bits are nums[1], and so
* on. Within each number, the most significant bit (bit 31) should
* come first, and the least significant bit (bit 0) should come last.
* That is, bits[0] should be bit 31 of nums[0], bits[1] should
* be bit 30 of nums[0], and so on.
*/
void numToBits(uint32_t * nums, int nNums, int * bits, int nBits) {
if (nBits != nNums * 32) {
printf("Invalid call to numToBits! nBits is %d, nNums is %d\n", nBits, nNums);
return;
}
for (int i = 0; i < nNums; i++) {
for (int j = 0; j < 32; j++) {
bits[i*32 + j] = getNthBit(nums[i], 31 - j);
}
}
}
void doTest(uint32_t * nums, int n) {
int bits[n *32];
numToBits(nums, n, bits, n*32);
for (int i =0; i < n; i++) {
printf(" %9d (%8X) => ", nums[i], nums[i]);
for (int j = 0; j < 32; j++) {
printf("%d", bits[i*32 + j]);
}
printf("\n");
}
}
int main(void) {
uint32_t array1[] = { 1, 2, 3, 4, 5, 15, 109};
uint32_t array2[] = { 123456789, 987654321 };
int bits[7*32-1];
doTest (array1, 7);
doTest (array2, 2);
numToBits(array1,7, bits , 7*32-1);
return EXIT_SUCCESS;
}
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