How to count the number of sub-sequences in a string?
This program is to count the number of sub-strings in a string.
Test case:
string ABCDCDC
pattern CDC
The answer should be 2 but I am getting 0.
def count_substring(string, sub_string):
for i in range(0,len(string)-len(sub_string)+1):
count=0
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
if j==len(sub_string):
count=count+1
return count
python string substring
edited Nov 21 '18 at 1:28
martineau
68.4k1090183
add a comment |
This program is to count the number of sub-strings in a string.
Test case:
string ABCDCDC
pattern CDC
The answer should be 2 but I am getting 0.
def count_substring(string, sub_string):
for i in range(0,len(string)-len(sub_string)+1):
count=0
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
if j==len(sub_string):
count=count+1
return count
python string substring
edited Nov 21 '18 at 1:28
martineau
68.4k1090183
Make sure your indentation is correct when you post...
– Julien
Nov 21 '18 at 0:05
add a comment |
This program is to count the number of sub-strings in a string.
Test case:
string ABCDCDC
pattern CDC
The answer should be 2 but I am getting 0.
def count_substring(string, sub_string):
for i in range(0,len(string)-len(sub_string)+1):
count=0
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
if j==len(sub_string):
count=count+1
return count
python string substring
edited Nov 21 '18 at 1:28
martineau
68.4k1090183
This program is to count the number of sub-strings in a string.
Test case:
string ABCDCDC
pattern CDC
The answer should be 2 but I am getting 0.
def count_substring(string, sub_string):
for i in range(0,len(string)-len(sub_string)+1):
count=0
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
if j==len(sub_string):
count=count+1
return count
python string substring
python string substring
edited Nov 21 '18 at 1:28
martineau
68.4k1090183
edited Nov 21 '18 at 1:28
martineau
68.4k1090183
edited Nov 21 '18 at 1:28
martineau
68.4k1090183
edited Nov 21 '18 at 1:28
martineau
68.4k1090183
edited Nov 21 '18 at 1:28
martineau
68.4k1090183
68.4k1090183
asked Nov 20 '18 at 23:43
user10628441
Make sure your indentation is correct when you post...
– Julien
Nov 21 '18 at 0:05
add a comment |
Make sure your indentation is correct when you post...
– Julien
Nov 21 '18 at 0:05
Make sure your indentation is correct when you post...
– Julien
Nov 21 '18 at 0:05
Make sure your indentation is correct when you post...
– Julien
Nov 21 '18 at 0:05
add a comment |
2 Answers
2
active
oldest
votes
At the end of the for j in range(0,len(sub_string)) loop j can be at most len(sub_string)-1 (if you don't break early). So if j==len(sub_string): is always False. You want if j==len(sub_string)-1: or simply else: (meaning you've reached the end of the for loop) instead.
Also count = 0 should be initialized at the start, not in the first for loop:
def count_substring(string, sub_string):
count=0
for i in range(0,len(string)-len(sub_string)+1):
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
else:
count=count+1
return count
answered Nov 20 '18 at 23:56
JulienJulien
7,67831637
add a comment |
Strings are sequences of 1-character substrings in Python, so you can use the built-in count() method — in other words, you don't have to re-invent the wheel and write your own function to do it.
test_string = 'ABCDCDC'
sub_string = 'CDC'
print(test_string.count(sub_string)) # -> 2
answered Nov 21 '18 at 1:20
martineaumartineau
68.4k1090183
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53403273%2fhow-to-count-the-number-of-sub-sequences-in-a-string%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
At the end of the for j in range(0,len(sub_string)) loop j can be at most len(sub_string)-1 (if you don't break early). So if j==len(sub_string): is always False. You want if j==len(sub_string)-1: or simply else: (meaning you've reached the end of the for loop) instead.
Also count = 0 should be initialized at the start, not in the first for loop:
def count_substring(string, sub_string):
count=0
for i in range(0,len(string)-len(sub_string)+1):
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
else:
count=count+1
return count
answered Nov 20 '18 at 23:56
JulienJulien
7,67831637
add a comment |
At the end of the for j in range(0,len(sub_string)) loop j can be at most len(sub_string)-1 (if you don't break early). So if j==len(sub_string): is always False. You want if j==len(sub_string)-1: or simply else: (meaning you've reached the end of the for loop) instead.
Also count = 0 should be initialized at the start, not in the first for loop:
def count_substring(string, sub_string):
count=0
for i in range(0,len(string)-len(sub_string)+1):
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
else:
count=count+1
return count
answered Nov 20 '18 at 23:56
JulienJulien
7,67831637
add a comment |
At the end of the for j in range(0,len(sub_string)) loop j can be at most len(sub_string)-1 (if you don't break early). So if j==len(sub_string): is always False. You want if j==len(sub_string)-1: or simply else: (meaning you've reached the end of the for loop) instead.
Also count = 0 should be initialized at the start, not in the first for loop:
def count_substring(string, sub_string):
count=0
for i in range(0,len(string)-len(sub_string)+1):
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
else:
count=count+1
return count
answered Nov 20 '18 at 23:56
JulienJulien
7,67831637
At the end of the for j in range(0,len(sub_string)) loop j can be at most len(sub_string)-1 (if you don't break early). So if j==len(sub_string): is always False. You want if j==len(sub_string)-1: or simply else: (meaning you've reached the end of the for loop) instead.
Also count = 0 should be initialized at the start, not in the first for loop:
def count_substring(string, sub_string):
count=0
for i in range(0,len(string)-len(sub_string)+1):
for j in range(0,len(sub_string)):
if(string[i+j]!=sub_string[j]):
break;
else:
count=count+1
return count
answered Nov 20 '18 at 23:56
JulienJulien
7,67831637
answered Nov 20 '18 at 23:56
JulienJulien
7,67831637
answered Nov 20 '18 at 23:56
JulienJulien
7,67831637
answered Nov 20 '18 at 23:56
JulienJulien
7,67831637
7,67831637
add a comment |
add a comment |
Strings are sequences of 1-character substrings in Python, so you can use the built-in count() method — in other words, you don't have to re-invent the wheel and write your own function to do it.
test_string = 'ABCDCDC'
sub_string = 'CDC'
print(test_string.count(sub_string)) # -> 2
answered Nov 21 '18 at 1:20
martineaumartineau
68.4k1090183
add a comment |
Strings are sequences of 1-character substrings in Python, so you can use the built-in count() method — in other words, you don't have to re-invent the wheel and write your own function to do it.
test_string = 'ABCDCDC'
sub_string = 'CDC'
print(test_string.count(sub_string)) # -> 2
answered Nov 21 '18 at 1:20
martineaumartineau
68.4k1090183
add a comment |
Strings are sequences of 1-character substrings in Python, so you can use the built-in count() method — in other words, you don't have to re-invent the wheel and write your own function to do it.
test_string = 'ABCDCDC'
sub_string = 'CDC'
print(test_string.count(sub_string)) # -> 2
answered Nov 21 '18 at 1:20
martineaumartineau
68.4k1090183
Strings are sequences of 1-character substrings in Python, so you can use the built-in count() method — in other words, you don't have to re-invent the wheel and write your own function to do it.
test_string = 'ABCDCDC'
sub_string = 'CDC'
print(test_string.count(sub_string)) # -> 2
answered Nov 21 '18 at 1:20
martineaumartineau
68.4k1090183
answered Nov 21 '18 at 1:20
martineaumartineau
68.4k1090183
answered Nov 21 '18 at 1:20
martineaumartineau
68.4k1090183
answered Nov 21 '18 at 1:20
martineaumartineau
68.4k1090183
68.4k1090183
add a comment |
add a comment |
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53403273%2fhow-to-count-the-number-of-sub-sequences-in-a-string%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Make sure your indentation is correct when you post...
– Julien
Nov 21 '18 at 0:05