34 lines
445 B
C
34 lines
445 B
C
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#include <stdio.h>
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// Function prototypes
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int bin2dec(int n);
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int pow2(int n);
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int main(void) {
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// Initialize variables
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int n;
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scanf("%d", &n);
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printf("%d\n", bin2dec(n));
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return 0;
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}
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int bin2dec(int n) {
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int ans = 0;
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int loc = 0;
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while (n != 0) {
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ans += pow2(loc) * (n % 10);
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n /= 10;
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loc++;
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}
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return ans;
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}
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int pow2(int n) {
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int ans = 1;
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for (int i = 0; i < n; i++) {
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ans *= 2;
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}
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return ans;
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}
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