How to copy part of a string from a specific character to the end of this string in VS 2015?

Question

The task is as follows. I need to enter 2 sentences, the second consists of 3 words, and the 2 and 3 words in the second sentence should be swapped. Here is the code itself on pure C (!), Added comments:

#include <stdio.h> #include <string.h> #include <conio.h> int main() { char str1[100] = "\0", str2[100] = "\0", str3[100] = "\0"; puts("Vvedite str1: "); gets(str1); puts("Vvedite str2: "); gets(str2); int i, n = 0, k = 0, h = 0, l = strlen(str2); //n - положение первого проблела //k - положение второго пробела //h - счетчик пробелов //l - количество букаф в str2 for (i = 1; i < l; i++) { if (str2[i] == ' ') { h++; if (h == 1) { n = i+1; } if (h == 2) { k = i+1; } } } //цикл поиска положения первого и второго пробела printf("\nn = %d, k = %d, h = %d, l = %d", n, k, h, l); int y = k - n; //y - количество букв во втором слове for (i = n + 1; i < k; i++) { strcpy_s(str3, y, str2); } //цикл, копипастирующий второе слово в str3, в котором есть ошибка ¯\_(ツ)_/¯ printf("\n", str3); _getch(); return 0; }

I work in a Visual Studio 2015 environment. And it requires writing some operators with underscores and "s" ("_s"). Normal strcpy can not be used, because there is some garbage with security. As I found out, strcpy_s has its own format, that is,

 strcpy_s('куда вставим', 'сколько байт копируем', 'откуда копируем');

But my compiler displays an error.

What needs to be corrected to complete the task (copy the second word -> paste it into str3)?

Nobody guesses how many characters you entered in str2 and how long it is for you in the end.
If you are given an exhaustive answer, mark it as correct (a daw opposite the selected answer).

Vladimir Martyanov Vladimir Martyanov 9,266 four 17 34 · Answer 1 · 2016-03-16T18:31:53

You misunderstood the documentation on strcpy_s: the second parameter shows not how much to copy, but how much the target buffer can accept . As a result, you can get a situation where y = 5, and str2 is longer than 5 characters. That is, the buffer cannot accept the string and an exception is thrown.

Nazarius Nazarius 33 five · Answer 2 · 2016-03-21T20:34:20

As it turned out, everything can be done in the usual algorithmic way.

 //здесь должен быть фрагмент кода от начала до счетчика пробелов int y = 0; //номер элемента str3 for (i = k; i < l; i++) { str3[y] = str2[i]; y++; } //копируем 3 слово в пустой массив str3[y] = ' '; //добавляем пробел y++; for (i = n; i < k; i++) { str3[y] = str2[i]; y++; } //копируем второе слово y = 0; //обнуляемся for (i = n; i < l; i++) { str2[i] = str3[y]; y++; } //начиная от первого пробела, заменяем второе и третье слово на содержимое str3 puts("\n"); puts(str2); //и да, не забывайте использовать puts и gets вместо printf и scanf //и т.д.

How to copy part of a string from a specific character to the end of this string in VS 2015?

2 answers 2

More articles: