20250707 baekjoon

code_study/Baekjoon/c/10828.c

@@ -0,0 +1,60 @@
+#define _CRT_SECURE_NO_WARNINGS
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+int opcodeToNum(char* opcode){
+    if(!strcmp(opcode, "push")) return 0;
+    if(!strcmp(opcode, "pop")) return 1;
+    if(!strcmp(opcode, "size")) return 2;
+    if(!strcmp(opcode, "empty")) return 3;
+    if(!strcmp(opcode, "top")) return 4;
+    return -1;
+}
+
+int main() {
+    int N;
+    scanf("%d",&N);
+    int* stack = (int*)malloc(sizeof(int)* N);
+    memset(stack,0,sizeof(int)*N);
+
+    int len = 0;
+    while(N--){
+        char str[13];
+        if (fgets(str, sizeof(str), stdin) == NULL) break;
+        if (str[0] == '\n') { N++; continue; }
+        str[strcspn(str, "\n")] = 0;
+        char *opcode = strtok(str, " ");
+        char *operend = strtok(NULL, " ");
+        int opNum = opcodeToNum(opcode);
+        int operendNum = operend ? atoi(operend) : 0;
+        
+        switch (opNum)
+        {
+        case 0:
+            stack[len] = operendNum;
+            len++;
+            break;
+        case 1:
+            if(len==0) {
+                printf("-1\n");
+            }
+            else {
+                printf("%d\n",stack[--len]);
+            }
+            break;
+        case 2:
+            printf("%d\n",len);
+            break;
+        case 3:
+            printf("%d\n", len ? 0 : 1);
+            break;
+        case 4:
+            printf("%d\n", len ? stack[len-1] : -1);
+            break;
+        }
+    }
+
+    free(stack);
+    return 0;
+}