[問題] return用法

看板C_and_CPP作者chot (C-hot)時間14年前 (2010/02/13 00:01)推噓6(6推 0噓 10→)

留言16則, 6人參與討論串1/1

#include <iostream> using namespace std; int binsearch(int * dset, int ib, int ie, int data) { cout << "search: ib = " << ib << ", ie = " << ie << endl; int ii; if (ib > ie) {ii = -1; } else { ii = (ib + ie) / 2; if (dset[ii] > data) { ii = binsearch(dset, ib, ii-1, data); } else if (dset[ii] < data) { ii = binsearch(dset, ii+1, ie, data); } } cout <<"search ib = "<<ib<<", ie = "<<ie<<" return: "<<ii<<endl; return ii; //回傳到哪呢? } int main() {int dset[] = {1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33}; cout << "Final data 13 is at: " << binsearch(dset,0,15,13) << endl; cout << "Final data 20 is at: " << binsearch(dset,0,15,20) << endl; return 0; system("pause"); } ======================================= 印出 search: ib = 0, ie = 15 search: ib = 0, ie = 6 search: ib = 4, ie = 6 search: ib = 6, ie = 6 search ib = 6, ie = 6 return: 6 search ib = 4, ie = 6 return: 6 //請問這行是如何印出的? search ib = 0, ie = 6 return: 6 search ib = 0, ie = 15 return: 6 Final data 13 is at: 6 search: ib = 0, ie = 15 search: ib = 8, ie = 15 search: ib = 8, ie = 10 search: ib = 10, ie = 10 search: ib = 10, ie = 9 search ib = 10, ie = 9 return: -1 search ib = 10, ie = 10 return: -1 search ib = 8, ie = 10 return: -1 search ib = 8, ie = 15 return: -1 search ib = 0, ie = 15 return: -1 Final data 20 is at: -1 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ※ 編輯: chot 來自: 218.172.87.94 (02/13 00:19)

推

VictorTom

02/13 00:24, , 1^F

02/13 00:24, 1^F

→

VictorTom

02/13 00:24, , 2^F

02/13 00:24, 2^F

→

VictorTom

02/13 00:25, , 3^F

02/13 00:25, 3^F