[백준] 1193. 분수 찾기

<아이디어>

x=1일때 (1,1)

x=2일때 (1,2)

x=4일때 (3,1)

.

 

x=(i*(i+1)/2)+1일때  i가 짝수면 (i+1,1), 홀수면 (1,i+1)

import sys
x=int(sys.stdin.readline())
for i in range(x):
    if ((i*(i+1))//2)+1<=x and (((i+1)*(i+2))//2)+1>x:
        break
a=(i+1)-(x-((i*(i+1))//2)-1)
b=1+(x-((i*(i+1))//2)-1)
if i%2==0:
    print(str(a)+"/"+str(b))
else:
    print(str(b)+"/"+str(a))