diff --git a/src/apple.c b/src/apple.c
index 766d543..44b0631 100644
--- a/src/apple.c
+++ b/src/apple.c
@@ -4,6 +4,15 @@ int n;
 int k;
 int A[100000];
 
+int p(int index[],int mid){
+    int sum = 0;
+    int a;
+    for(a=0;a<n;a++){
+        //切り上げにする
+        sum = sum + (index[a]+mid-1)/mid;
+    }
+    return sum;
+}
 
 int main(){
   int i, lb, ub;
@@ -11,7 +20,18 @@ int main(){
   for(i = 0; i < n; i++){
     scanf("%d", &A[i]);
   }
-
-
+  lb = 0;
+  ub = 1000000000;
+  while(ub - lb > 1){
+    int mid = (lb + ub)/2;
+    //ここで評価する
+    if(p(A, mid) <= k){
+        ub = mid;
+    }
+    else{
+        lb = mid;
+    }
+  }
+  printf("%d\n",ub); 
   return 0;
 }
diff --git a/src/array.c b/src/array.c
index 13ed925..8984083 100644
--- a/src/array.c
+++ b/src/array.c
@@ -11,8 +11,17 @@ int main(){
   for(i = 0; i < n; i++){
     scanf("%d", &A[i]);
   }
-
-
-
+  lb = -1;
+  ub = n;
+  while(ub - lb > 1){
+      int mid = (lb + ub)/2;
+      if(A[mid] >= k){
+          ub = mid;
+      }
+      else{
+          lb = mid;
+      }
+  }
+  printf("%d\n",ub); 
   return 0;
 }
diff --git a/src/spear.c b/src/spear.c
index 766d543..afe0680 100644
--- a/src/spear.c
+++ b/src/spear.c
@@ -4,6 +4,15 @@ int n;
 int k;
 int A[100000];
 
+int p(int index[],int mid){
+    int sum = 0;
+    int a;
+    for(a=0;a<n;a++){
+        //切り捨てで考える
+        sum = sum + index[a]/mid;
+    }
+    return sum;
+}
 
 int main(){
   int i, lb, ub;
@@ -11,7 +20,18 @@ int main(){
   for(i = 0; i < n; i++){
     scanf("%d", &A[i]);
   }
-
-
+  lb = 0;
+  ub = 1000000001;
+  while(ub - lb > 1){
+    int mid = (lb + ub)/2;
+    if(p(A, mid) < k){
+        ub = mid;
+    }
+    //k以上になった時に下限を上げて終了条件
+    else{
+        lb = mid;
+    }
+  }
+  printf("%d\n",lb); 
   return 0;
 }
diff --git a/src/works.c b/src/works.c
index 766d543..82b6ef7 100644
--- a/src/works.c
+++ b/src/works.c
@@ -4,6 +4,34 @@ int n;
 int k;
 int A[100000];
 
+int p(int index[],int mid){
+    int sum = 0;
+    //人数のカウント、これとkを比較し評価
+    int count = 1;
+    int a;
+    for(a=0;a<n;a++){
+        if(mid>=index[a]){
+        	sum=sum+index[a];
+        	//仕事量がmid超えるか確認
+        	if(sum>mid){
+        		//次の人に移る
+        		count=count+1;
+        		//次の仕事を保存
+        		sum=index[a];
+        	}
+        }
+        else{
+        	//ありえないパターン
+        	return k+1;
+        }
+    }
+    if(count>k){
+    	return k+1;
+    }
+    else{
+    	return count;
+    }
+}
 
 int main(){
   int i, lb, ub;
@@ -11,7 +39,18 @@ int main(){
   for(i = 0; i < n; i++){
     scanf("%d", &A[i]);
   }
-
-
+  lb = 0;
+  ub = 1000000000;
+  while(ub - lb > 1){
+    int mid = (lb + ub)/2;
+    //ここで評価する
+    if(p(A, mid) <= k){
+        ub = mid;
+    }
+    else{
+        lb = mid;
+    }
+  }
+  printf("%d\n",ub); 
   return 0;
 }