Commite7fea38

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+15

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lines changed

+15

-11

lines changed

Lines changed: 8 additions & 6 deletions

Original file line number	Diff line number	Diff line change
`@@ -11,18 +11,20 @@ Returns the index of the first occurrence of needle in haystack, or -1 if needle`
`11`	`11`
`12`	`12`	`##思路`
`13`	`13`
`14`		`-题意是从主串中找到子串的索引，如果找不到则返回-1，我们只需要遍历主串长度减子串长度即可，利用substring比较即可。`
	`14`	`+题意是从主串中找到子串的索引，如果找不到则返回-1，当字串长度大于主串，直接返回-1，然后我们只需要遍历比较即可。`
`15`	`15`
`16`	`16`	```java
`17`	`17`	`classSolution {`
`18`	`18`	`publicintstrStr(Stringhaystack,Stringneedle) {`
`19`		`-int l1= haystack.length(), l2= needle.length(), l3= l1- l2;`
`20`		`-for (int i=0; i<= l3;++i) {`
`21`		`-if (haystack.substring(i, i+ l2).equals(needle)) {`
`22`		`-return i;`
	`19`	`+int l1= haystack.length(), l2= needle.length();`
	`20`	`+if (l1< l2)return-1;`
	`21`	`+for (int i=0; ; i++) {`
	`22`	`+for (int j=0; ; j++) {`
	`23`	`+if (j== l2)return i;`
	`24`	`+if (i+ j== l1)return-1;`
	`25`	`+if (haystack.charAt(i+ j)!= needle.charAt(j))break;`
`23`	`26`	`}`
`24`	`27`	`}`
`25`		`-return-1;`
`26`	`28`	`}`
`27`	`29`	`}`
`28`	`30`	```

Lines changed: 7 additions & 5 deletions

Original file line number	Diff line number	Diff line change
`@@ -10,13 +10,15 @@`
`10`	`10`	`*/`
`11`	`11`	`publicclassSolution {`
`12`	`12`	`publicintstrStr(Stringhaystack,Stringneedle) {`
`13`		`-intl1 =haystack.length(),l2 =needle.length(),l3 =l1 -l2;`
`14`		`-for (inti =0;i <=l3; ++i) {`
`15`		`-if (haystack.substring(i,i +l2).equals(needle)) {`
`16`		`-returni;`
	`13`	`+intl1 =haystack.length(),l2 =needle.length();`
	`14`	`+if (l1 <l2)return -1;`
	`15`	`+for (inti =0; ;i++) {`
	`16`	`+for (intj =0; ;j++) {`
	`17`	`+if (j ==l2)returni;`
	`18`	`+if (i +j ==l1)return -1;`
	`19`	`+if (haystack.charAt(i +j) !=needle.charAt(j))break;`
`17`	`20`	`}`
`18`	`21`	`}`
`19`		`-return -1;`
`20`	`22`	`}`
`21`	`23`
`22`	`24`	`publicstaticvoidmain(String[]args) {`

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