import sys from time import clock f=open('in11_3.txt','r') f1=open('out_23_11_3.txt','w') begin=clock() n=int(f.readline()) m=f.readline().split(',') sum=(n*(n+1))/2 for i in range(0,len(m)): sum=sum-int(m[i]) f1.write(str(sum)+"\n") f1.write("time"+str(clock()-begin)) f.close() f1.close()