23 lines
309 B
C
23 lines
309 B
C
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#include <stdio.h>
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// Function prototypes
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int calculate(int a);
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int main(void) {
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// Initialize variables
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int n;
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scanf("%i", &n);
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// Calculate answer
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printf("%i\n", calculate(n));
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return 0;
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}
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int calculate(int a) {
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if (a == 0) {
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return 1;
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} else {
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return calculate(a - 1) - a + a * 2;
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}
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}
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