diff --git a/binary-search/12015/jinho.js b/binary-search/12015/jinho.js
new file mode 100644
index 0000000..863706e
--- /dev/null
+++ b/binary-search/12015/jinho.js
@@ -0,0 +1,37 @@
+const fs = require('fs');
+const input = fs.readFileSync('a.txt').toString().trim().split('\n');
+
+const N = parseInt(input[0]);
+const data = input[1].split(' ').map(e => parseInt(e));
+
+const answer = [data[0]];
+
+const binarySearch = ( arr, elem ) => {
+    let left = 0;
+    let right = arr.length - 1;
+    let idx;
+    while( left <= right ){
+        let mid = Math.floor((left + right) / 2);
+        if ( arr[mid] === elem ){
+            return -1;
+        }   
+        else if ( arr[mid] < elem ) {
+            left = mid + 1;
+        }   
+        else if ( arr[mid] > elem ) {
+            right = mid - 1;
+        }
+    }
+    arr[left] = elem;
+}
+
+for (let i=1; i<data.length; i++){
+    if ( data[i] > answer[answer.length -1] ){
+        answer.push(data[i]);
+    }   
+    else if ( data[i] < answer[answer.length - 1] ){
+        binarySearch(answer, data[i]);
+    }
+}
+
+console.log(answer.length)
\ No newline at end of file
diff --git a/binary-search/1300/jinho.js b/binary-search/1300/jinho.js
new file mode 100644
index 0000000..499ef35
--- /dev/null
+++ b/binary-search/1300/jinho.js
@@ -0,0 +1,30 @@
+const fs = require('fs');
+const input = fs.readFileSync('a.txt').toString().trim().split('\n');
+
+const N = parseInt(input[0]);
+const M = parseInt(input[1]);
+
+let left = 1;
+let right = M;
+
+const countLessOrEqual = (x) => {
+    let cnt = 0;
+    for (let i=1; i<N+1; i++){
+        cnt += Math.min( Math.floor(x/i), N ) ;
+    }
+    return cnt;
+}
+while (left < right){
+    let mid =  Math.floor((left+right)/2);
+    // console.log("mid : ", mid);
+    
+    const count = countLessOrEqual(mid);
+    // console.log("count : ", count);
+    if ( M > count ){
+        left = mid + 1;
+    }   else {
+        right = mid;
+    }
+}
+
+console.log(left);
\ No newline at end of file
diff --git a/binary-search/1920/jinho.js b/binary-search/1920/jinho.js
new file mode 100644
index 0000000..e95a314
--- /dev/null
+++ b/binary-search/1920/jinho.js
@@ -0,0 +1,26 @@
+const fs = require('fs');
+const input = fs.readFileSync('/dev/stdin').toString().trim().split('\n');
+
+const M = parseInt(input[0]);
+const N = parseInt(input[2]);
+
+const data = input[1].split(' ');
+const comparison = input[3].split(' ');
+
+const obj = {};
+const answer = [];
+for(let i=0; i<M; i++){
+    if (!obj[data[i]]){
+        obj[data[i]] = 1;
+    }
+}
+
+for (let i=0; i<N; i++){
+    if (obj[comparison[i]]){
+        answer.push(1);
+    }   else {
+        answer.push(0);
+    }
+}
+
+console.log(answer.join('\n'));
\ No newline at end of file
diff --git a/binary-search/19637/jinho.js b/binary-search/19637/jinho.js
new file mode 100644
index 0000000..b103807
--- /dev/null
+++ b/binary-search/19637/jinho.js
@@ -0,0 +1,33 @@
+const fs = require('fs');
+const input = fs.readFileSync('a.txt').toString().trim().split('\n');
+
+const N = Number(input[0].split(' ')[0]);
+const M = Number(input[0].split(' ')[1]);
+
+const ranks = [];
+const scores = [];
+for (let i=1; i<N+1; i++){
+    ranks.push(input[i].split(' ')[0]);
+    scores.push(Number(input[i].split(' ')[1]));
+}
+
+const answer = [];
+const binarySearch = (x) => {
+    let left = 0;
+    let right = N;
+    
+    while ( left < right ){
+        let mid = Math.floor((left + right)/2);
+        if (x > scores[mid]){
+            left = mid + 1;
+        }   else {
+            right = mid ;
+        }
+    }
+    return ranks[left];
+}
+
+for (let i=N+1; i<N+M+1; i++){
+    answer.push(binarySearch(Number(input[i])));    
+}
+console.log(answer.join('\n'));
\ No newline at end of file