init commit

2024-03-19 01:05:51 +08:00
commit 199bbf2628
393 changed files with 34883 additions and 0 deletions
--- a/archive/algorithm/leetcode/8.c
+++ b/archive/algorithm/leetcode/8.c
@ -0,0 +1,108 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <math.h>
+/**
+ * https://leetcode-cn.com/explore/interview/card/top-interview-questions-easy/5/strings/37/
+ * 字符串转整数（atoi）
+ */
+#define INT_MIN -2147483648
+#define INT_MAX 0x7fffffff
+int myAtoi(char *str)
+{
+    long long ret = 0;
+    char flag = 1, len = 0;
+    while (*str == ' ') //删除空
+    {
+        str++;
+    }
+    if (*str == '-')
+    {
+        flag = -1;
+        str++;
+    }
+    else if (*str == '+')
+    {
+        str++;
+    }
+    else if (*str < '0' || *str > '9')
+    {
+        return 0;
+    }
+    while (*str >= '0' && *str <= '9' && len < 11)
+    {
+        ret = ret * 10 + (*str - '0');
+        str++;
+        if (ret != 0)
+        {
+            len++;
+        }
+    }
+    ret *= flag;
+    if (ret < INT_MIN)
+    {
+        return INT_MIN;
+    }
+    if (ret > INT_MAX)
+    {
+        return INT_MAX;
+    }
+    return ret;
+}
+/*
+int myAtoi(char* str) {
+    if(strlen(str)==0)
+        return 0;
+    char* xianzai= str;
+    long long fanhui = 0;
+    int flag = 1;//记录符号位正负
+    long long max = pow(2,31)-1;
+    long long min = pow(2,31);//溢出的上下界不相同
+    while (*xianzai == ' ')
+    {
+        xianzai++;//跳过空格位置
+    }
+    if (*xianzai == '-')
+    {
+        flag = -1;
+        xianzai++;
+    }
+    else if(*xianzai == '+')
+    {
+        xianzai++;
+    }
+    else if (*xianzai < '0' || *xianzai > '9')
+    {
+             return 0;
+    }
+    while (*xianzai >= '0' && *xianzai <= '9')
+    {
+        fanhui= fanhui*10;
+        fanhui=fanhui+*xianzai-'0';//利用符号本身的ascii码直接转换成数字
+        if(flag==1 && fanhui>max)
+        {
+            //正数溢出，返回INT_MAX
+            return max;
+        }
+        else if(flag==-1&&fanhui>min)
+        {
+            return min;//注意int类型上下界数值上相差1
+        }
+        xianzai++;
+    }
+    return flag*fanhui;
+}
+*/
+int main()
+{
+    printf("%d\n", myAtoi("-1"));
+    printf("%d\n", myAtoi("456"));
+    printf("%d\n", myAtoi("   -42"));
+    printf("%d\n", myAtoi("a65r"));
+    printf("%d\n", myAtoi("9223372036854775808"));
+    printf("%d\n", myAtoi("-91283472332"));
+    printf("%d\n", myAtoi("4193 with words"));
+    printf("%ld,%ld\n", -pow(2, 31), pow(2, 31) - 1);
+    getchar();
+    return 0;
+}