21 lines
372 B
C
21 lines
372 B
C
#include <stdio.h>
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int factorials[10] = {0};
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int factorial(int n) {
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if (factorials[n-1] == 0) {
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factorials[n-1] = n * factorial(n-1);
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}
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return factorials[n-1];
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}
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int main() {
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int k = 0, sum = 0, i;
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scanf("%d", &k);
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factorials[0] = 1;
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for (i = 1;i <= k; i++) {
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sum += factorial(i);
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}
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printf("%d", sum);
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return 0;
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} |