added xor

Home/PL/HW/Stack Calculator/lib.c

@@ -0,0 +1,74 @@
+#include "head.h"
+
+void print_plates(Plate *plates)
+{
+    if (plates == NULL)
+    {
+        printf("[%p]\n", plates);
+        return;
+    }
+    while(plates){
+        printf("[%14p]->[%14p] ", plates, plates->next);
+        printf("data: [%4d]\n", plates->x);
+        plates = plates->next;
+    }
+    printf("-------------\n");
+}
+
+Plate* push(Plate* plates, int d){
+    Plate *temp = NULL;
+    if((temp=malloc(sizeof(Plate)))==NULL){
+        perror("malloc:NULL");
+        exit(2);
+    }
+    temp->x = d;
+    if(plates==NULL) temp->next=NULL;
+    else{
+        temp->next=plates;
+    } 
+    return temp;
+}
+
+Plate* del_head(Plate* plates){
+    Plate *temp=plates;
+    if(plates==NULL) return NULL;
+    if(plates->next==NULL){
+        free(plates);
+        return NULL;
+    }
+    plates = plates->next;
+    free(temp);
+    return plates;
+}
+
+int len(Plate* plates){
+    int ans = 0;
+    Plate *temp = plates;
+    if(plates==NULL) return 0;
+    while(temp){
+        ans++;
+        temp=temp->next;
+    }
+    return ans;
+}
+
+int pop(Plate** plates){
+    int i;
+    if(*plates==NULL){
+        printf("Error");
+        exit(4);
+    }
+    i = (*plates)->x;
+    *plates = del_head(*plates);
+    return i;
+}
+
+int isnm(char *str){
+    int i = 0, n = strlen(str);
+    for(i=0; i<n; i++){
+        if(!isdigit(str[i])){
+            return 0;
+        }
+    }
+    return 1;
+}