- 1#include 2 int main() 3 {
- 4 int n,
- i,
- t;
- 5 float q,
- s;
- 6
- while (scanf("%d%f", &n, &q) == 2) 7 {
- 8
- if (n >= 2 && n <= 20 && q > 0 && q < 2) 9 {
- 10 s = 0;
- 11
- for (i = 0; i <= n; i++) 12 {
- 13 s = s + pow(q, i);
- 14
- }
- 15 printf("%.3f\n", s);
- 16
- }
- 17
- }
- 18 19
- }
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