弟弟的作业 （C语言代码）

#include "stdio.h"                      

#include "string.h" 

int stoi(int n, char s[])

{

int a = 0,t=1;

while (n--)

{

a += t*(s[n]-'0');

t *= 10;

}

return a;

}

int fun(int n, char s[])

{

char num[4][4] = { 0 };

int i, j=0,flag=0;

for (i = 0; i < n; i++)

{

if ((s[i] != '+') && (s[i] != '-')&& flag == 0)

{

num[0][j++] = s[i];

}

else if(flag == 0)

{

num[1][0] = s[i];

j = 0;

flag = 1;

continue;

}

if ((s[i] != '=')&& flag == 1)

{

num[2][j++] = s[i];

}

else if (flag == 1)

{

j = 0;

flag = 2;

continue;

}

if (((s[i] == '?') || (s[i] >= '0') && (s[i] <= '9')) && flag == 2)

{

if (s[i] == '?')

return 0;

else

num[3][j++] = s[i];

}

}

if (num[1][0] == '+')

{

if (stoi(strlen(num[0]), num[0])+ stoi(strlen(num[2]), num[2])== stoi(strlen(num[3]), num[3]))

return 1;

else

return 0;

}

else

{

if (stoi(strlen(num[0]), num[0]) - stoi(strlen(num[2]), num[2]) == stoi(strlen(num[3]), num[3]))

return 1;

else

return 0;

}

}

int main()

{

char s[10] = { 0 };

int c = 0, len;

while (scanf("%s", s) != EOF)

{

len = strlen(s);

if (fun(len, s) == 1)

c++;

memset(s, 0, sizeof(s));

}

printf("%d", c);

return 0;

}