题解 | #挑7#

#include <stdio.h> #include <string.h>

int main(void) { int n = 0; int i = 0; int cnt = 0; int temp = 0; while(scanf("%d", &n) != EOF) { cnt = 0; for(i = 6; i <= n; i++) {

        if(i % 7 == 0)
        {
            cnt++;
        }
        else
        {
            temp = i; 
            while(temp)
            {
                if(temp % 10 == 7)
                {
                    cnt++;
                    break;
                }
                temp = temp/10;
            }
        }
    }
    printf("%d", cnt);
}

return 0;

}