#include int main() { int fusecount; scanf("%d", &fusecount); int fuses[fusecount]; for (int i = 0; i < fusecount; i++) scanf("%d", &fuses[i]); float burntimes[fusecount * 3]; int counter = 0; for (int i = 0; i < fusecount; i++) { for (int j = 0; j < 3; j++) { // for each state, (dont light, light, light both ends) if (j == 0) burntimes[counter] = 0; else if (j == 1) burntimes[counter] = fuses[i]; else if (j == 2) burntimes[counter] = (float)fuses[i] / 2.0; counter++; } } for (int i = 0; i < counter/2; i++) { for (int j = counter-1; j > counter/2; j--){ printf("%f %f\n", burntimes[i], burntimes[j]); } } }